b. Both the Kelvin and Celsius scales have the same size degree unit , option c and d correctly describe the three temperature scales and their relationship to each other
The Celsius scale, also recognised as the centigrade scale, is a thermal scale based on zero degrees Celsius for the freezing temperature and one hundred degrees Celsius for the water's boiling point. Anders Celsius, a Swedish physicist, astrophysicist, and engineer, invented (and is named after) this magnitude. The centigrade scale was decided to name after Swedish astrophysicist Anders Celsius (1701-1744), who proposed it in 1742. The family name is derived from the name of a estate, Latin celsus ("mound"). The Kelvin scale. A temperature scale that starts at zero (-273.15°C or -459.67°F). Each degree, or kelvin, symbolises one degree of temperature rise on the Celsius scale. Water freezes at 273.15 K and heats at 373.15 K on the Kelvin scale.
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in applying this method to other reactions, could the reactant mole ratio for all reactions be found using this method
The reactant mole ratio for all reactions discovered using this method must be met in order to apply this method to other reactions. Furthermore, the reactant molar ratios for each reaction must be known in order to determine the mole ratio in which the principal reactants react.
To adjust the reaction temperature, water was added to reaction mixtures A through E. In this experiment, KCr,O- was chosen as the source of dichromate ions because it is a strong oxidising agent that is easily converted into dichromate ions.The mole ratio is the ratio of the mole amounts of any two compounds in an equitable chemical reaction. The balance chemical equation compares the ratios of the molecules required to complete the reaction. It calculates how much of one substance is required to produce a certain amount of another substance using the mole ratios between the different parts of the reaction.
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. when the colors yellow and blue are combined, they produce a green color. which statement most likely describes the relative sizes of the yellow and blue food-coloring molecules in the diagram?
students in a biology class are studying the effects of temperature on the aquatic plant elodea. They count the number of oxygen. bubbles released by an elodea plant in a beaker of water heated to different temperatures
From the given graph plotting the rate of photosynthesis versus the temperature, the rate of oxygen production is greatest at the point M.
What is photosynthesis?Photosynthesis is the biochemical process of synthesising chemical energy by green plants with the aid of light energy. The photosynthetic reaction involves the combination of carbon dioxide and water producing oxygen gas and glucose.
The chemical energy is stored in plants in the form of glucose which is then break down by the need of energy forming ATP. The photosynthetic reaction is affected by the temperature and pressure of the atmosphere.
From the graph, it is clear that, the rate of photosynthesis is higher at the point M. Higher the rate of photosynthesis, higher will be the oxygen production. Hence, option B is correct.
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Post-Lab Questions Discuss the outcome of Ihe E1 and E2 reactions for (he following: Which alkene was formed as Ihe major product? Explain thoroughly for full credit; Which alkene was formed as the minor product? Explain thoroughly for full credit;
Both E1 reaction and E2 reaction are more likely to produce 2-methyl-2-butene, instead of 2-methyl-1-butene.Therefore, it makes sense that "2-methyl-2-butene" is the major product while "2-methyl-1-butene" is the minor product because it is not as stable or substituted.
This has happened due of Zaitsev's Rule. Compared to 2-methyl-1-butene, 2-methyl-2-butene's double bond is more heavily replaced. Because it is more stable, 2-methyl-2-butene is more prevalent in the yield. The hydrogen needed to create 2-methyl-2-butene comes from the beta carbon that has undergone the most substitutions. According to Zaitsev's rule, the main product is the one produced as a result of hydrogen being lost during beta distillation, errors being made when weighing and measuring reagents and products, gathering the distillate above 45 C, and alkene products being lost because the alkenes were too close to a heat source. Future investigations should aim to reduce these flaws to obtain more precise results.
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The figure below shows the rotation curves of several spiral galaxies, extending to the very edge of their visible disks. What do these curves tell us about the distribution of dark matter in these galaxies?
Group of answer choices
Most of the dark matter is in the bulge.
Most of the dark matter is in the galaxies’ outskirts.
Most of the dark matter is near stars.
Most of the dark matter is in clumps.
The thing that the curves tell us about the distribution of dark matter in these galaxies is option B: Most of the dark matter is in the galaxies’ outskirts.
Why do galaxy rotation curves suggest the existence of dark matter?Beyond the visible borders of galaxies, the velocity of stars remains relatively constant, suggesting that there must be more matter present than what we can see as stars and gas.
When the impact of DE became noticeable, the rotation curves are shown to dip at a specific distance. r. These flat, v = constant, rotation curve data suggest that the amount of dark matter is increasing linearly with r up to great distances from the spiral galaxies' centers.
From the graph you can see they all pointing or going one direction, hence we can deduce that it is option B.
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For each trial, calculate the moles of KHP used to neutralize the NaOH solution and put the answer in the Results Table. (Hint: Use the correct formula from the Discussion section to calculate the molar mass of KHP! It is NOT the mass of K + H + P!)
For each trial, using the mole ratio from the balanced equation, calculate the moles of NaOH and put the answer in the Results Table.
For each trial, calculate the molar concentration of the NaOH solution and put the answer in the Results Table. (See example in the discussion.)
Calculate the average molarity and enter this answer in your Results Table.
Submit your Results Table and Calculations in the following corresponding question boxes.
1.Moles of KHP for Trial 1,2,3,4
2.Moles of NaOH for Trial 1,2,3,4
3.Molarity of NaOH (M) for trial 1,2,3,4
4. Average Molarity of NaOH (M)
1. The number of moles of KHP is found by dividing the mass of KHP by the molecular weight of KHP.
2. The number of moles of NaOH is found by multiplying the moles of KHP by the mole ratio of NaOH to KHP given by the above, balanced chemical reaction.
It will be presumed that more KHP is present in the solution if additional NaOH is added. As a result, the % KHP will be higher than anticipated. If the concentration of NaOH is doubled, just half the volume from the initial experiment is needed. To titrate NaOH with KHP, add NaOH from the burette to a predetermined amount of KHP. The mass and volume of KHP utilized to create the KHP solution are used to calculate the molarity of the KHP solution. The molarity of the NaOH is then determined using the information from the titration.
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a reaction that has a large equilibrium constant has hints a. a faster reaction rate than a reaction with a small equilibrium constantb. more reactants then products at equilibriumc. more products then reactants at equilibriumd. equal amounts of products and reactants at equilibrium.
When the rates of the forward and reverse reactions are identical, equilibrium has occurred. At equilibrium, the concentrations of each reactant and product are both constant.
The relationship between a reaction's products and reactants at equilibrium is expressed by the equilibrium constant, K. A rise in pressure will cause the reaction to move to the right if there are more reactants than products by moles. It is untrue that a reaction with a higher equilibrium constant value proceeds more quickly than one with a lower equilibrium constant value. The equilibrium constant's value has no bearing on the reaction's rate. The rate constant affects the reaction's rate.
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Oxalic acid (HC2H2O4HC2H2O4) is a weak acid found in the leaves of rhubarb. Which of the following solutions will have the highest pH?
a) 0.00075 M H2C2O40.00075 M H2C2O4
b) 1.0×10−4 M1.0×10−4 M H2C2O4H2C2O4
c) 1.0 M H2C2O41.0 M H2C2O4
d) 0.5 M H2C2O4
b) 1.0×10−4 M1.0×10−4 M H2C2O4H2C2O4 will have the Highest pH among the solutions.
When compared to strong acid, does oxalic acid produce less H ions?A weak acid is what oxalic acid is. It is not as strong as H3O+ ion (water). However, it is more potent than acids like acetic, sulfuric, nitrous, and benzoic. First of all, it is an organic substance, and organic substances are often not strong acids. Dicarboxylic acid is another name for oxalic acid.
How can you determine the pH of an amalgamation of weak bases and weak acids?Similar to how the weak acid in the example was calculated, a weak base's solution can also be calculated to determine its pH. However, the concentration of the hydroxide ion will be represented by the variable x.
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25
Mutations are changes in the DNA of an organism. Changes caused by mutations can affect the structure and function of different proteins in the body. Three changes caused by mutations are described below:
Having two different-colored eyes is caused by a mutation that results in increased or decreased pigmentation in one of the eyes. While this mutation affects the coloration of the eye, it does not affect how the eye functions.
Cystic fibrosis is caused by the mutation of a protein in the lungs that causes a sticky mucus to build up in the lung tissue. This build up of mucus can make it difficult for a person to breathe.
Bone density can be affected by a mutation. This mutation can cause very dense bones that are almost unbreakable.
What is true about mutations in organism?
A.
Changes caused by mutations never have an effect on an organism's cells.
B.
Changes caused by mutations can be harmful, beneficial, or neutral to an organism.
C.
Changes caused by mutations always have positive effects on an organism.
D.
Changes caused by mutations always have negative effects on an organism.
Bone density can be affected by a mutation. This mutation can cause very dense bones that are almost unbreakable therefore the true statement about mutations in organism is that changes caused by mutations can be harmful, beneficial, or neutral to an organism which is therefore denoted as option B.
What is Mutation?This is referred to as a change in the DNA sequence of an organism and it occurs when there are errors during cell division.
The changes caused have different effects on the organisms which could be harmful, beneficial, or neutral.
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What is the maximum theoretical mass of ammonia that can be made from 300g of hydrogen gas?
The maximum theoretical mass of ammonia production from 300g of hydrogen gas is equal to 1700 g.
What is theoretical yield of the chemical reaction?The theoretical yield of the chemical reaction can be explained as the quantity of product formed in a reaction evaluated from stoichiometric calculations.
Given the reaction of the formation of ammonia from hydrogen gas:
3H₂ (s) + N₂ (g) → 2NH₃ (g)
The molecular mass of the ammonia = 17 g/mol
Given the mass of the hydrogen gas = 300 g
The number of moles of the hydrogen gas = 300/2 = 150 mol
From the above equation, 2 moles of ammonia are produced from 3 moles of hydrogen gas.
150 mol of hydrogen gas will produce ammonia = (2/3) ×150 = 100mol
The mass of ammonia is produced = 100 × 17 = 1700 g
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from the list below, select four situations in which casting is the preferred fabrication technique. (1) for alloys having low ductilities (2) when it is the most economical fabrication technique (3) when it is needed to join a large variety of metals and alloys (4) for large pieces and/or complicated shapes (5) for economical producing of parts that require very close dimensional tolerances (e.g. bushing and gears) (6) when mechanical strength is not an important consideration (2), (3), (5), (6) (1), (2), (4), (6) (2), (3), (4), (6) (1), (2), (4), (5) (1), (3), (4), (5)
Mechanical strength isn't a key factor when a wide range of metals and alloys need to be joined.
What are the three primary fabrication methods?While many metal fabrication businesses employ a variety of methods, the majority rely on the three fundamental operations of cutting, bending, and assembly.
What is a fabrication, exactly?The following are some illustrations of fabrication or falsification: producing data artificially when it ought to be coming from a real experiment Unauthorized tampering with or fabrication of information, texts, pictures, audio, video, music, or other works.
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the half equivalence point is in the middle of the buffer region. in order to reach the half equivalence point in their titration, veronica needed to add 24.47 ml of koh to 50.00 ml of 0.368 m hf. what is the concentration of conjugate base at the half equivalence point? note: do not use scientific notation or units in your response. sig figs will not be graded in this question, enter your response to four decimal places. carmen may add or remove digits from your response, your submission will still be graded correctly if this happens.
The concentration of conjugate base at the half equivalence point should be 0.347 M.
Moles of HF = molarity × volume ( in L )
= 0.342 × 50/1000
= 0.0171 mol
Since, at half equivalence point, exactly half of the acid in the buffer solution has reacted with the titrants.
So, moles of KOH = 0.0171/2 mol
molarity of KOH = moles / volume (in L)
= (0.0171 / 2 mol) / 24.63 L / 1000
= 0.0171 × 1000 / 2 × 24.63
= 0.347 M
Therefore, the concentration of conjugate base at the half equivalence point is 0.347 M.
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35. What is the set up used to determine the average atomic mass of Boron in #34?
A. (10 + 11) /2
B. (10 x .20) + (11 x .80)
C. 11 + 10
D. (10 x .20) + (11 x .80) /2
Answer: B
Explanation: 2 isotopes of boron are present.
Let percent abundance of B-10 is x
percent abundance of B-11 is (100-x)
Average atomic mass,
[tex]10.80=\frac{x*10+(100-x)*11}{100}[/tex]
[tex]10.80=\frac{10x+1100-11x}{100}[/tex]
[tex]1080=1100-x[/tex]
[tex]x=20[/tex]
how many grams of al(s) are needed to produce 154.6 g of al2o3 if the percent yield for this reaction is 87.5%. assume that there is excess o2.
44.98 grams of al(s) are needed to produce 154.6 g of al2o3 .
briefly:-4 Al(s) + 3 O₂(g) → 2 Al₂O₃(s)
mass obtained of an Al₂O₃ (experimental yield) is 154..6 g.
Theoretical yield of an Al₂O₃ is x g.
Calculate the percent yield of Al₂O₃ using the following expression.
%yield = (experimental yield / theoretical yield) × 100%
(154..6 / x) × 100% = 87.8%
theoretical yield= 176.08
molar mass of Al₂O₃ is 101.96 g/mol
mass of Al = 26.98 u*176.08/101.96= 44.98g
How is the yield rate calculated?A bond's yield is a number that represents the return on investment. The formula yield = coupon amount/price can be used to compute yield in its most basic form.
How is yield calculated?Yield calculation methods The stock or bond's market value or original investment should be determined. Identify the profit the investment produced. Subtract the income from the market value. Add 100 to this amount.
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nitrogen monoxide is produced by combustion in an automobile engine. according to the following reaction, how many grams of oxygen gas are necessary to form 0.154 moles nitrogen dioxide?
The nitrogen monoxide produced by the combustion in the automobile engine. the grams of the oxygen gas are used to form the 0.154 moles of the nitrogen dioxide is 2.46 g.
The reaction is given below :
2NO + O₂ ---> 2NO₂
2 moles of the NO₂ produce by the 1 moles of O₂
moles of the of NO₂ = 0.154 mol
moles of the O₂ = (1/2) × 0.154
= 0.077 mol
molar mass of O₂ = 32 g/mol
mass of O₂ = moles × molar mass
= 0.077 × 32
= 2.46 g
The mass of oxygen gas needed to form the nitrogen dioxide is 2.46 g.
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According to simple valence bond theory (no promotion/hybridization), which of the following species would not form a bond with carbon? Consider the electronic configuration of the ground state of the element
(a) LiC
(b) BeC
(c) BC
(d) C2
(e) CN
BeC will will not form a pair because no free element is available with Be.
The elements given in the above question is as follow,
Now consider the ground state of given element we get,
[tex]Li=1s^2,2S^1\\Be=1s^2,2S^2\\B=1s^2,2S^2,2p^1\\C=1s^2,2S^2,2p^2\\N=1s^2,2S^2,2p^3[/tex]
Now, for balance bond theory,
Consider,
a) LiC
[tex]Li=1S^2,2S^1\\C=1S^2,2S^2,2P^2[/tex]
It will form a bond because unpaired electrons are present.
b)Bec
[tex]Be=1s^2,2S^2\\C=1s^2,2S^2,2p^2[/tex]
If will not form a pair because no free element is available with Be.
c)BC
[tex]B=1s^2,2S^2,2p^1\\C=1s^2,2S^2,2p^2[/tex]
It will form a bond because unpaired electrons are present in Boron and carbon.
d)[tex]C_2[/tex]
[tex]C=1s^2,2S^2,2p^2[/tex]
It will form a bond because unpaired electrons are present.
e)CN
[tex]C=1s^2,2S^2,2p^2\\N=1s^2,2S^2,2p^3[/tex]
It will form a bond because unpaired electrons are present.
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During the molecular modeling lab, you were told to consider the importance that molecular geometry has on polarity. Which of the following list of molecules would you classify as polar? [Hint: It may be helpful to sketch the structures to determine polarity.] I. PF5 II. SF4 III. SiO2 IV. H2S V. CI2 O II + IV O I + III O III + IV O IV + IO III
Molecules (II) and (IV) that is SF4 and H2S are polar.
In polar molecules, the electron density is unevenly distributed throughout the molecule, resulting in some regions of negative charge and some regions of positive charge. Molecular polarity depends on both individual bond polarities and molecular geometry, the latter of which can be predicted using his VSEPR theory.
Reason :
In molecule (I), molecule is symmetrical all polar bond cancel out polarity of each other so molecule is non-polar.
In molecule (II), molecule is asymmetrical, having a lone pair so molecule is polar.
In molecule (III), molecule is linear, bond polarity cancel out each other, so molecule is non-polar.
In molecule (IV), molecule is bent (asymmetric) having two lone pair, molecule is polar.
In molecule (V), no bond polarity, hence molecule is non-polar.
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A chemist decomposes samples of several compounds; the masses of their constituent elements are shown. Calculate the empirical formula for each compound. a. 1.651 g Ag, 0.1224 g O b. 0.672 g Co, 0.569 g As, 0.486 g O c. 1.443 g Se, 5.841 g Br
The empirical formula for each compound are as follow,
a)[tex]Ag_2 O[/tex]
b)[tex]Co_3As_2O_8[/tex]
c)[tex]SeBr_4[/tex]
As per the data share in the above question are as follow,
The mass of their constituent elements are as follow,
a) Ag=1.651 g
O=0.1224 g
b)Co =0.672 g
As =0.569 g
O=0.486 g
c) Se =1.443 g
Br =5.841 g
We have to calculate the empirical formula for each compound.
a)Now Moles of (given mass upon Molar mass) [tex]Ag=\frac{1.651}{108} =0.015 \:moles[/tex]
Moles of [tex]O=\frac{0.1224}{8\times 2} =0.0077 \:moles[/tex]
Smallest mole value [tex]0.0077 \:moles[/tex]
Divide all component by smallest mass.
Therefore [tex]Ag \Rightarrow\frac{0.015}{0.0077} \rightarrow2\\\\O \Rightarrow\frac{0.0077}{0.0077} \rightarrow1[/tex]
Combine to get empirical formula,
[tex]Ag_2 O[/tex]
b)Now Moles of (given mass upon Molar mass) [tex]Co=\frac{0672}{59} =0.011 \:moles[/tex]
Moles of [tex]As=\frac{0.569}{75} =0.0076\: moles[/tex]
Moles of [tex]O=\frac{0.486}{16} =0.0304 \:moles[/tex]
Smallest mole value [tex]0.0076 \:moles[/tex]
Divide all component by smallest mass.
Therefore
[tex]Co \Rightarrow\frac{0.011}{0.0076} \rightarrow1.5\rightarrow1.5 \times 2\rightarrow3\\\\As \Rightarrow\frac{0.0076}{0.0076} \rightarrow1\rightarrow1 \times 2\rightarrow2\\\\O \Rightarrow\frac{0.0304}{0.0076} \rightarrow4\rightarrow4 \times 2\rightarrow8[/tex]
Combine to get empirical formula,
[tex]Co_3As_2O_8[/tex]
c)Now Moles of (given mass upon Molar mass) [tex]Se=\frac{1.443}{79} =0.018 \:moles[/tex]
Moles of [tex]Br=\frac{5.841}{80} =0.073 \:moles[/tex]
Smallest mole value [tex]0.018 \:moles[/tex]
Divide all component by smallest mass.
Therefore
[tex]Se \Rightarrow\frac{0.018}{0.018} \rightarrow1\\\\Br \Rightarrow\frac{0.073}{0.018} \rightarrow4[/tex]
Combine to get empirical formula,
[tex]SeBr_4[/tex]
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using xuv series what can you deduct about relationship between iodized energy and reactivity of metals
Using xuv series, deduct about relationship between iodized energy and reactivity of metals that, The first ionization energy of a metal has little bearing on its reactivity.
Ionization energy, sometimes referred to as ionization potential, is the amount of energy needed to remove an electron from an isolated atom or molecule in physics and chemistry. Ionization energies are related with the removal of each subsequent electron, however they are most frequently employed when the first (and loosely held) electron is removed. In an electric discharge tube, when a quickly moving electron produced by an electric current collides with a gaseous atom of the element, causing it to eject one of its electrons, the ionization energy of a chemical element, given in joules or electron volts, is often measured. A hydrogen atom, which consists of an orbiting electron connected to a nucleus of one proton, requires one ionization energy of 1018 joules (13.6 electron volts) to completely expel an electron. The amount of an element's ionization energy depends on a number of factors, including the size of the atom, its electronic make-up, and the electric charge of its nucleus. Alkali metals are the simplest chemical elements to remove an electron from, whereas noble gases are the most difficult.
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What is ΔH∘rxn for the following chemical reaction?
CO(g)+NH3(g)→HCN(g)+H2O(g)
You can use the following table of standard heats of formation (ΔH∘f) to calculate the enthalpy of the given reaction.
Element/ Compound Standard Heat of Formation (kJ/mol) Element/ Compound Standard Heat of Formation (kJ/mol)
H(g) 218 N(g) 473
H2(g) 0 O2(g) 0
NH3(g) −45.90 O(g) 249
CO(g) −110.5 H2O(g) −241.8kJ
C(g) 71 HCN(g) 130.5kJ
C(s) 0 HNO3(aq) −206.6
Express the standard enthalpy of reaction to three significant figures and include the appropriate units.
To calculate the standard enthalpy of reaction (ΔH∘rxn) for the given chemical reaction, we need to use the equation for enthalpy of reaction, which is:
ΔH∘rxn = Σ(ΔH∘f products) - Σ(ΔH∘f reactants)
where ΔH∘f is the standard heat of formation for a given compound, and the summation symbol (Σ) indicates that we need to sum the values for all of the products and reactants in the reaction.
In this case, we are given the standard heats of formation for the products and reactants in the reaction:
CO(g)+NH3(g)→HCN(g)+H2O(g)
We can use these values to calculate the enthalpy of reaction, as follows:
ΔH∘rxn = Σ(ΔH∘f products) - Σ(ΔH∘f reactants)
= (ΔH∘f HCN + ΔH∘f H2O) - (ΔH∘f CO + ΔH∘f NH3)
= (130.5 kJ + −241.8 kJ) - (−110.5 kJ + −45.90 kJ)
= (−111.3 kJ) - (−156.4 kJ)
= 45.1 kJ
Therefore, the standard enthalpy of reaction for the given chemical reaction is 45.1 kJ to three significant figures. This value represents the amount of heat that is absorbed or released when the reactants are converted into products, and it can be used to predict the energetics of the reaction under standard conditions.
States of Matter
Heating Curve Calculation
144.29 g of pentane vapor at 117 °C is cooled
to completely solid at -84 °C.
Heating Curve Data for Pentane
Boiling Point (°C)
Melting Point (°C)
AHp (kJ/mol)
vap
AHfus (kJ/mol)
Specific Heat, gas (J/mol K)
Specific Heat, liquid (J/mol K)
117
-84
45.3
9.3
120
168
How much heat is released
from the system as the
pentane cools?
A 157 kJ
B. 177 kJ
C. 67600 kJ
D. 67.5 kJ
The amount of heat released from the system as the pentane cools is 67.5kJ.
What is the formula for calculating heat absorbed by pentane?To determine the heat released from the system as the pentane cools, we need to consider the heat absorbed or released during each of the phase changes (vaporization and fusion) as well as the heat absorbed or released during the temperature change of the substance in each phase.
The heat absorbed or released during a phase change can be calculated using the enthalpy of vaporization (AHvap) or enthalpy of fusion (AHfus) and the number of moles of substance undergoing the phase change.
The heat absorbed or released during a temperature change can be calculated using the specific heat of the substance and the number of moles of substance and the temperature change.
In this case, we can first calculate the heat absorbed or released during the vaporization of the pentane:
Heat = ΔHvap * moles
Heat = 45.3 kJ/mol * 144.29 g / (58.12 g/mol) = 102.1 kJ
Next, we can calculate the heat absorbed or released during the cooling of the pentane vapor to the melting point:
Heat = specific heat * moles * temperature change
Heat = 168 J/mol K * 144.29 g / (58.12 g/mol) * (117 - (-84)) K = 68400 J = 68.4 kJ
Then, we can calculate the heat absorbed or released during the fusion of the pentane:
Heat = ΔHfus * moles
Heat = 120 kJ/mol * 144.29 g / (58.12 g/mol) = 270 kJ
Finally, we can calculate the heat absorbed or released during the cooling of the pentane from the melting point to the final temperature:
Heat = specific heat * moles * temperature change
Heat = 168 J/mol K * 144.29 g / (58.12 g/mol) * (-84 - (-84)) K = 0 J
The total heat released from the system can be calculated by adding up the heat absorbed or released during each of these processes:
Total heat = 102.1 kJ + 68.4 kJ + 270 kJ + 0 kJ = 440.5 kJ
The correct answer is therefore D) 67.5 kJ.
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Phenacaine HCI 1% w/v Chlorobutanol 0.5% w/v 1.9% Boric Acid Solution ad 60 mL Make isotonic solution using boric acid. Sig. One drop in each eye. (Please use White-Vicent Method) (a) What are the needed amount of phenacaine HCl and chlorobutanol? (b) What is the required volume of 1.9% boric acid? (c) If you do not have 1.9% boric acid solution and have to compound from boric acid powder
A)The needed amount of phenacaine HCl is 0.6g and chlorobutanol is 0.3 g B) 40.8 ml is the required volume of 1.9% boric acid C) 0.7752 grams you do not have 1.9% boric acid solution and have to compound from boric acid powder
A)for calculating amount. of drug requieed Amount of phenacine Hcl SO = 1% w/v measure 19 in 100 ml
60/100×1g= 0.6 gm
Amount of chlorobutanol = 0.5% w/v means 0.5g in 100 ml.
So 0.5g ⇒100ms
>> 60/100 ×0.5g = 0.39gm
b) so total volume
= Yol
At Vol. B
= 7.2ml + 12
= 19-2nd
So Volume Boric acid
= total volume of solution - volume of drug
= 60ml - 19.2ml
= 40.8gm
c) in this preparation. we need
40.8 ml = 0.4089 of Nac to =0.77529 grams boric acid powder to 40.8 ml
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in calorimetry, whatever happens in the system, the exact same change must occur to the surroundings.
In calorimetry, whatever happens in the system, the exact same change must occur to the surroundings is False.
What occurs in calorimetry?
Heat transfer rates to or from a substance are measured using calorimetry. Heat is transferred to do this using a calibrated item (calorimeter). Calculating the quantity of heat transmitted by the process under study requires using the temperature change recorded by the calorimeter.
The sealed calorimeter has thermometers that track temperature changes as a reaction takes place. This closed system functions similarly to a chemical reactor.
It's crucial to realize that in calorimetry difficulties, the material reacting is the "system," whilst the surroundings are made up of water and calorimetry. The heat exchanged between the "system" and "surroundings" is what is measured.
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Classify the radicals into the appropriate categories. Primary Secondary Tertiary Allylic Answer Bank (CH3)2CHCH2CH2 HC H3C H3C
The formation of free radicals in the organic reaction takes place when the bond is cleavage homolytically. Free radicals are species with a single electron and thus, they are electron deficient in nature.
A free radical may be primary, secondary or tertiary depending upon the number of H-atoms attached to it. Further, the free radicals may be categorized as alkyl, allyl or benzyl radicals.
Primary free radicals: When radical is attached to two H-atoms.
Secondary free radicals: When radical is attached to one H-atoms.
Tertiary free radicals: When radical is not attached to any H-atoms.
Allylic free radicals: When radical is attached to two H-atoms and is in conjugation (resonance) with double bond.
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look at the given synthesis and the provided reagents. fill in the blanks with the single letter code of the appropriate reagent, or the appropriate descriptive vocabulary word/phrase to complete the description. remember the computer is very literal so check your spelling carefully.
The reagent are used in the chemical reaction to cause the chemical reaction or the test performed if one occurred.
The reagents are the compounds or the mixture that are added to the chemical reaction in order to start the chemical reaction. The reagent is not necessarily be consumed during the chemical reaction. the reagent is used to identify the compound or to measure the substance if it is present in the reaction.
The reagent is the initiator , solvent , catalyst etc. the example of the reagents are : Tollen's reagent , Fehling's reagent , Fenton's reagent and collins reagent etc.
The question is incomplete, I answer the question in general according to my knowledge.
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Question 4
How many moles of CuSO4 are there in 7.87 x 1024 molecules of CuSO4?
Answer:
8058.88
Explanation:
7.87 x 1024 = 8058.88
duh
What is the mass percentage of C in morphine, C₁7H19NOs? Provide an
answer to two decimal places.
The mass percentage of C in morphine would be 4.21%.
What is mass percentage?The mass percentage of a composition in a compound is the mass of the composition relative to the mass of the entire compound. This can be mathematically expressed as:
Mass percentage = mass of component/mass of substance x 100%
In this case, we are looking for the mass percentage of C in [tex]C_{17}H_{19}NO_3[/tex].
Molar weight of C = 12 g/mol
Molar mass of [tex]C_{17}H_{19}NO_3[/tex] = (12x17) + (1x19) + (14x1) + (16x3)
= 285 g/mol
Mass percentage of C = 12/285
= 4.21% to 2 decimal places.
In other words, the mass percentage of C in morphine is 4.21%.
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Which of the following compound(s) could be used as starting material(s) make an amide in just 1 step, using reactions we learned in Chapter 21? Select all that apply! O an ester O a carboxylic acid O a nitrile O an anhydride another amide O an acid chloride
The correct answer is carboxylic acid. Option B.
In a similar reaction, a coupling agent such as DCC can be used to prepare amides by the reaction of carboxylic acids with amines. Simple amides can be made by reacting acid anhydrides with amines. Finally, amides can be formed from the direct reaction of carboxylic acids and amines.
Amides are generally prepared by coupling a carboxylic acid with an amine using a coupling agent or by first converting the carboxylic acid to a derivative. Alternative methods include Staudinger ligation, aminocarbonylation of aryl halides, and oxidative amidation of aldehydes. Amides can be hydrolyzed in the presence of aqueous acids.
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Nuclides below the valley of stability can become more stable through which of the following processes?
A) beta emission
B) positron emission
C) gamma emission
D) electron capture
E) neutron bombardmentB) positron emission
Nuclides below the valley of stability can become more stable through positron emission.
A positron emission tomography (puppy) test is an imaging check which can assist reveal the metabolic or biochemical feature of your tissues and organs. The puppy test uses a radioactive drug (tracer) to reveal both ordinary and abnormal metabolic pastime.
A positron is the anti-particle of a beta particle, and is emitted with the aid of a proton-rich nucleus. The collision of an electron and a positron yields two 0.511 MeV gamma rays. Positron gamma radiation can penetrate via inches of iron, concrete, timber, plastic, water, and many others.
They're converted into two high-electricity gamma rays moving immediately faraway from every other.
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help asha balance the following equation by completing the equation with the correct numbers: co equation c co2
The Balanced Eqn is 2CO+O2→2CO2.
A chemical reaction is a method wherein one or more materials, also called reactants, are transformed into at least one or more special substances, called merchandise. Materials are both chemical elements or compounds.
A few synthesis reactions can result in more than one product. Photosynthesis is one of the maximum important chemical reactions on earth. It allows plants and a few microbes to transform water and carbon dioxide gas into storable sugar and oxygen.
Chemical compounds are made from atoms of different elements, joined collectively through chemical bonds. A chemical synthesis normally involves the breaking of existing bonds and the formation of recent ones.
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