The pH during the titration 20.0 mL OF 0.1000 M NaOH(aq) with 0.1000 M HCOOH(aq) of after 8.68 mL of the base is added is 3.074
The pH of the titration can be calculate as follows;
First we should calculate the number of moles,
moles of NaOH = 0.1000 M * 20.00 mL = 2.0 mmol
of moles of HCOOH = 0.1000 M * 8.68 mL = 0.868 mmol
Then we can calculate concentration of excess acid
concentration of excess acid = [(moles acid - molesbase]/V tota
concentration of excess acid = [(2.0 mmol- 0.868 mmol)/(28.68 mL)
concentration of excess acid = 3.94 x 10⁻³ M.
the we can calculate the pH
For weak acids;
[H⁺] = √Ka.C = √(1.8 x 10⁻⁴)(3.94 x 10⁻³ M) = 8.42 x 10⁻⁴ M.
pH = - log[H⁺].
pH = - log( 8.42 x 10⁻⁴ ) = 3.074
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What do you call a substance that can only be separated into two or more simpler substances using chemical changes?
Answer:
Compounds are substances composed of two or more elements chemically combined that can be separated into simpler substances only by chemical means. Water, for example, is a compound because pure water is composed of only H2O molecules.
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which two activities can a student perform to show the formation of soil through chemical processes?
There are several activities that a student can perform to show the formation of soil through chemical processes. Here are two examples:
Soil pH experiment: In this activity, the student can measure the pH of soil samples collected from different locations or layers. The pH of the soil is an indicator of the soil's acidity or alkalinity, which is influenced by chemical processes such as the breakdown of organic matter and the weathering of minerals. By comparing the pH of different soil samples, the student can observe how chemical processes can affect the properties of soil.
Soil horizons experiment: In this activity, the student can create a soil profile by layering soil samples collected from different depths in a jar or container. The student can then observe the different layers, or horizons, that form in the soil profile over time. These horizons are formed through a variety of chemical processes, including the weathering of minerals, the breakdown of organic matter, and the leaching of nutrients. By observing these horizons, the student can see how chemical processes contribute to the formation and development of soil.
It's important to note that these are just a couple of examples, and there are many other activities that a student can perform to demonstrate the formation of soil through chemical processes.
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There are several activities that a student can perform to show the formation of soil through chemical processes. Here are two examples:
Soil pH experiment: In this activity, the student can measure the pH of soil samples collected from different locations or layers. The pH of the soil is an indicator of the soil's acidity or alkalinity, which is influenced by chemical processes such as the breakdown of organic matter and the weathering of minerals. By comparing the pH of different soil samples, the student can observe how chemical processes can affect the properties of soil.
Soil horizons experiment: In this activity, the student can create a soil profile by layering soil samples collected from different depths in a jar or container. The student can then observe the different layers, or horizons, that form in the soil profile over time. These horizons are formed through a variety of chemical processes, including the weathering of minerals, the breakdown of organic matter, and the leaching of nutrients. By observing these horizons, the student can see how chemical processes contribute to the formation and development of soil.
It's important to note that these are just a couple of examples, and there are many other activities that a student can perform to demonstrate the formation of soil through chemical processes.
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consider the following two compounds: c5h11oh (1-pentanol) c5h11sh (1-pentanethiol) which compound has the higher molar mass? which compound has the higher boiling point?
1-pentanethiol has a higher molar mass.
What is Boiling Point?
The boiling point of a liquid is the temperature at which its vapour pressure equals that of the surrounding air. The liquid turns to a vapour at this temperature.
The boiling point of the liquid is influenced by the atmospheric pressure. When a liquid is at high pressure, its boiling point is higher than when it is at atmospheric pressure. Different liquids have variable boiling points at a certain pressure. The standard boiling point of a liquid was established by IUPAC in 1982 as the temperature at which a liquid starts to boil at a pressure of one bar.
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The element gallium (Ga) freezes at 29.8 ∘C, and its molar enthalpy of fusion is ΔHfus=5.59kJ/mol.When molten gallium solidifies to Ga(s) at its normal melting point, is ΔS positive or negative?Calculate the value of ΔS when 70.0 g of Ga(l) solidifies at 29.8 ∘C.Express the change in entropy in joules per kelvin to three significant digits.
The enthalpy of fusion is defined as the enthalpy change that occurs when a substance changes from a solid to a liquid at its melting point. The value of ΔS for molten gallium is 1.29 J/K.
The equation for calculation of ΔS is given as,
ΔS = ΔHfus / T
where, ΔHfus is the molar enthalpy of fusion and T is the temperature at which the process occurs.
In the above case, given that,
T = 29.8° C = 303.15 K
Substituting these values we get,
ΔS = (5.59 kJ/mol) / (303.15 K) = 0.0185 J/K
The change in entropy is positive which is because the substance is changing from a more ordered state (a solid) to a less ordered state (a liquid).
For calculating the change in entropy when 70.0 g of Ga(l) solidifies at 29.8° C, we can use the equation given below,
ΔS = m × ΔS/mol
where, m is the mass of the substance in grams, and ΔS/mol is the change in entropy per mole of the substance.
In the above case, given that
m = 70.0 g
ΔS/mol = 0.0185 J/K
Substituting the values we get,
ΔS = (70.0 g) × (0.0185 J/K) = 1.29 J/K
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write the net ionic equation for powdered iron added to a solution of iron (iii) sulfate
Answer: Fe + H2SO4 = Fe2(SO4)3 + H2 (Note: Dilute H2SO4)
Explanation:
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What is the relationship among the efficieny output work and input work of a machine?
The efficiency of a machine is the ratio of the output work it performs to the input work required to operate it. This ratio is expressed as a percentage, and it tells you how much of the input work is converted into useful output work.
For example, if a machine requires 10 units of input work to perform 5 units of output work, its efficiency would be 50%. This means that 50% of the input work is converted into useful output work, while the remaining 50% is lost as waste heat, friction, or other forms of energy dissipation.
In general, the efficiency of a machine is determined by its design, as well as the materials and components used to construct it. Machines that are well-designed and constructed with high-quality materials will typically have higher efficiencies than those that are poorly designed or made with lower-quality materials.
It's also important to note that the efficiency of a machine can vary depending on the type and amount of work it is performing. For example, a machine may be more efficient at performing certain tasks than others, or it may become less efficient as it wears out or is subjected to heavy use.
PLEASE HELP: write a balanced reaction formula that shows what happens when methane is burned in air.
The reaction that shows the combustion of methane is given by;
[tex]CH_{4} (g) + 2O_{2} (g) --------- > CO_{2}(g) + 2H_{2}O(g)[/tex]
What is a combustion reaction?We know that a combustion reaction is the kind of reaction that occurs when a substance is burnt in oxygen. We know that the burning of a substance on oxygen would lead to the oxidation of the product.
In the case of an organic compound like methane, when the substance has been burnt in oxygen, the products of the reaction are now carbon dioxide and water. This are the oxidation products of the combustion.
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which of the two systems on the right, upland or lowland, is characterized by a stable equilibrium?
Neither of the two systems on the right, upland or lowland, is characterized by a stable equilibrium.
Uplands and lowlands are parts of plains that are classified based on their height above sea level. Lowlands are usually below 200 m (660 ft), while highlands range from 200 m (660 ft) to 500 m (1,600 ft).
Upland soils have a sandy loam texture, but vary in rock and organic matter content depending on the location of the landscape. Upland soils develop on top of moraine deposits of base-rich volcanic rock and support orthotic, brunisolein, or dark gray rubisol.
The Lowland series consists of very deep and well-drained soils formed by great volcanic and slope flooding. These soils are found in fans, mountains and hills. The slope is 4-60%.
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In the electroplating of nickel, 0.200 faraday of electrical charge is passed through a solution of NiSO4. What mass of nickel is deposited?
a. 2.94
b. 5.87
c. 11.7
d. 58.7
When a solution of NiSO4 is exposed to a 0.2 faraday electrical charge, b. 5.87 g of nickel, Ni is deposited.
The Balanced equation is :
Ni²⁺ + 2e —> Ni
To Determine the mass of the Ni when there is 0.2 farad.
According to the balanced equation,
The molar mass of nickel is 1× 59 [tex]gmol^{-1}[/tex]
The number of farad =2
(Since, In the balanced equation nickel losses 2 electron. )
2 farad = 59 [tex]gmol^{-1}[/tex] of nickel
0.2 farad = ?
⇒[tex]\frac{(59)(0.2)}{2}[/tex]
⇒5.87 [tex]gmol^{-1}[/tex] ≈ 5.9 [tex]gmol^{-1}[/tex]
What is Nickel Electroplating ?Nickel is deposited onto a metal component by the technique of nickel electroplating. Before plating can start, parts must be clean and free of debris, corrosion, and flaws. A mixture of heat treating, cleaning, masking, pickling, and etching may be used to prepare and protect the part before plating.
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9. Why did your water appear to boil at a temperature less than 100°C? Use the definition of temperature to
help with your answer.
The boiling requires overcoming air pressure with vapor pressure, the boiling temperature of water depends on your height from sea level. Additionally, although this tends to raise the boiling point, it relies on the presence of contaminants in the water.
However, water boils at sea level at a temperature of 100 degrees Celsius. It serves as a definition. Because that is what the Celsius system is founded on, that temperature was picked. Actually, the temperature that pure liquid water at sea level cannot get above is 100 degrees Celsius, which is the most that it can be heated to before plateauing. The "boiling point" measures the actual object in question.
If you gauge the temperature from the first sign of boiling, it may occur at a little lower levels. Whisps of vapor may be seen around 90–95 degrees, but if you are at sea level with a reliable thermometer and clear water, the temperature should increase to 100 and remain there until the water starts to boil.
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Which of the following are routes of chemical exposure?
A Ingestion.
B Inhalation.
C Skin absorption.
D All of the above.
Answer
DExplaniationExposure to chemicals may occur by the following routes:inhalation,ingestion,contact with skin and eyes, or. injection.All of the above are the routes of chemical exposure to the body.
There are 3 routes of chemical exposure and pollutants:
inhaling
absorption
ingesting
One is exposed to chemicals and pollutants when one inhale (breathe in). This number can be much higher for infants and children. The chemicals and pollutants you inhale can end up in your lungs and blood stream.
Absorption
One can be exposed to chemicals and pollutants by coming into contact with them through your skin and eyes. These organs can be more sensitive to chemicals and may react more quickly than the rest of your body.
Ingesting
One is exposed to chemicals and pollutants when you eat and drink. Chemicals and pollutants are found in both our food and water sources.
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imagine the electrolysis of a molten sample of alcl3 in its pure state. how many faradays of electricity would be required to produce a mole of metallic aluminum in such a process?
There are 3 faradays of electricity that would be required to produce a mole of metallic aluminum in such a process.
Aluminum is a chemical element with the symbol Al and atomic number 13. The density of aluminum is lower than other common metals, about one-third that of steel. It has a high affinity for oxygen and forms a protective oxide layer on the surface when exposed to air.
One of several chemical elements that are usually lustrous solids that conduct heat and electricity and can be formed into plates and the like. The American Chemical Society officially adopted aluminum in 1925, but in 1990 the International Union of Pure and Applied Chemistry accepted aluminum as an international standard. And we end up with English-speaking North Americans using aluminum today.
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The molecule O=C=S) is linear and has a Lewis structure analogous to that of CO2. Would you expect this molecule to be nonpolar?
The molecule O=C=S is linear and has a Lewis structure analogous to that of CO2. This molecule is polar molecule.
What are polar molecules?
Polar molecules are molecules that have two oppositely charged ends. Polar molecules exist as a result of differences in the electronegativities of the atoms of the elements found in the molecule.
With two electron domains around the central atom .the electron domain & molecular geometries are linear .sinces oxygen is more electronegative than sulphur.
The bond dipole symmetrically distributed around the carbon atom , are not identical and therefore,the bond dipole do not sum to zero.
Therefore, OCS molecule is a polar molecule not a non polar.
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if you have 25 ml of a buffer solution at an initial ph, and it takes 13 ml of 0.1m hcl to change the buffer to ph -1, what is the buffer capacity for this solution
If you have 25 ml of a buffer solution at an initial ph, and it takes 13 ml of 0.1m hcl to change the buffer to ph -1, 130 ml/M is the buffer capacity for this solution.
The buffer capacity of a solution is a measure of its ability to resist changes in pH when small amounts of acid or base are added. It is defined as the amount of acid or base that must be added to the solution to change its pH by one unit.
To find the buffer capacity of a solution, we need to know the initial pH of the solution and the amount of acid or base required to change its pH by one unit.
In this case, we are given that the initial pH of the buffer solution is some value, and it takes 13 mL of 0.1 M HCl to change the pH by 1 unit. We can use this information to calculate the buffer capacity as follows:
Buffer capacity = amount of acid or base required to change pH by 1 unit / concentration of acid or base
= 13 mL / 0.1 M
= 130 mL/M
Therefore, the buffer capacity of this solution is 130 mL/M.
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What substance would precipitate if you were to add a saturated sodium carbonate solution to a saturated sodium chloride solution? Why?
NaCl + Na₂CO₃ ⇌ NaCl + Na₂CO₃
Answer:
Explanation: This is an example of a double displacement reaction. Here sodium carbonate is added to sodium chloride. The result is no visible reaction.
There is no effect of mixing the solids. Mixing solutions would have little effect unless they were at very high concentrations, then it is possible some sodium carbonate would precipitate due to the common ion effect.
g ethyl butyrate is produced in 70% yield once equilibrium is established under the conditions above. describe briefly two different things you could do to increase the yield of ester beyond 70%.
Two different things you could do to increase the yield of ester beyond 70% are increase ethanol and butyric acid or enzymes involved in the reaction .
Define esterification.
The general term for a chemical reaction in which two reactants (usually an alcohol and an acid) combine to create an ester as the end product is "esterification." Esters are frequently found in organic chemistry and biological materials, and they frequently have a distinctive, fruity scent.
By increasing one of the reactants' concentration, the yield of ester can be increased (either the alcohol or the carboxylic acid). A surplus of one reactant will cause the reaction to move to the right in accordance with Le Chatelier's Principle, increasing the generation of ester and, consequently, the yield of ester.
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A buffer solution is prepared that is 0.18 M NH3 and 0.27 M NH4Cl. What is the pH of this buffer? Kb for NH3 is 1.8 x 10-5
A. 4.57
B. 9.26
C. 9.43
D. 4.92
E. 9.08
Option E is Answer. The pH value of the buffer is 9.08
The pH of a solution: It is a measure of hydrogen ion concentration, which in turn is a measure of its own acidity. Pure water dissociates slightly into equal concentrations of hydrogen and hydroxyl (OH−) ions.
The pH is then calculated using the expression:
pH = - log [OH-].-------------(1)
the pH of acidic buffer =pka+log[ acid/salt]
the pH of basic buffer =pkb+log[ base/salt]
Given that Kb=1.8x10^-5
base=0.27M
salt=0.18M
first, we have to calculate the value of kb,
pkb=−log[1.8×10 ^−5]
pkb=4.74
The pH of buffer=pkb+log[base/salt]-------------(2)
We find out the value of kb and now substitute it in equation(2)
pOH=4.74+log[ 0.27/0.18]
=4.74−0.176=4.92
pH=14−4.92=9.08
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The half-life for radioactive decay (a first-order process) of plutonium-239 is 24,000 years.How many years would it take for one mole of this radioactive material to decay so that just one atom remains?
The half-life for the radioactive decay of plutonium-239 is 24,000 years. 1.896 x 10⁶ years it will take for one mole of this radioactive material to decay.
Half life of plutonium-239 = 24,000 years
Number of years of one-mole material decay = ?
For this, we will use the following equation
k = 0.693 ÷ t 1/2
k = 0.693 ÷ 24000 years
k = 0.000028875
Now find it for 1 atom
n = 6.023 x 10²³ atoms which is equal to 1 mole
There for n-x = 1
now
t = ( 1 ÷ k) × ln( n ÷ n-x)
t = ( 1 ÷ 0.000028875) × ln( 6.023 x 10²³ ÷ 1)
t = 1.896 x 10⁶ years
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What patterns do you notice in valance electrons configuration as you moved through elements #3-#18?.
The distribution of electrons among the orbital shells and subshells is shown in the electron configuration of an atom.
What electron configuration exists in group 18 of period 3?
• According to the Periodic Table, P3- has the same electrical configuration as argon, the following Noble gas (Group 18) element, which is 2,8,8.
• The number of valence electrons in groups 1-2 and 13-18 rises by one from one element to the next across the periodic table's rows, or periods.
•There are several different arrangements for electrons. There should be two distinct trends or patterns: The number of valence shell electrons is constant for elements belonging to the same Group. Along a Periodic Table period, valence electrons are added in increasing numbers from left to right.
• Phosphorus (symbol P) has an atomic number of 15, according to a periodic table or table of elements.
Thus, there are 15 protons in each atom. Lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium are the chemical elements that make up alkali metals (Fr).
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gas is placed in a balloon with a volume of 3.0 l at 35oc and 800 torr. what would be the new volume for the gas if placed under stp?
gas is placed in a balloon with a volume of 3.0 l at 35oc and 800 torr. what would be the new volume for the gas if placed under stp The new volume will be "13.0 L" when the balloon is inflated to less than 800 mmHg.
Ideal gas formula
The answer to the query is
P1 = 1 atm for pressure
P₂ = 1.053 atm
T1 = 273.15 K for the temperature.
T₂ = 373.15 K
V1 = 10.0 L of volume
The ideal gas equation can be used to:
⇒ PV = nRT
or,
Then,
The new book will be:
→ V₂ =
By changing the values above,
=
= 13.0 L
Consequently, the strategy described above is appropriate.
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the water took longer to evaporate. what does this imply about the strength of the attraction of the molecules to each other?
The strength of attraction of the water molecules to each other is the hydrogen bonding.
The slowest evaporating liquid might be the water. Water 's hydrogen bonding, being the most powerful sort of intermolecular force, might be the toughest to triumph over to break out into the fueloline kingdom and could bring about the longest time. Hydrogen bonds do not form in all molecules because hydrogen can only form these bonds with highly electronegative atoms. It is a weak type of force that happens when a hydrogen atom is bonded to an atom which has a high electronegativity.
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what is the ph of a solution with [h3o+] = 3.0 × 10-3 m?
The ph of a solution with [h3o+] = 3.0 × 10-3 m is 2.52.
A solution's acidity can be determined by looking at its pH, which is a measurement of hydrogen ion concentration. Pure water slightly separates into ions with roughly equal amounts of hydrogen and hydroxyl (OH) ions. [H+] is 107 for a neutral solution, or pH = 7.
You need to know the hydronium ion concentration in moles per litre to determine the pH of an aqueous solution (molarity). The equation pH = - log [H3O+] is then used to determine the pH.
You can alternatively write the pH Formula as. l o g [H +] = p H Problems With the pH Formula. Problem 1: Determine the pH of the solution in which there are 8.0 10-8M hydronium ions.
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The complete question is ''What is the pH of a solution with [ H3O+] = 3.0 × 10-3 M?
A) 3.0 × 10-3
B) 2.52
C) 3.0
D) -2.52
E) 9.0
B) 2.52
what volume of hydrogen gas is produced when 96.7 g of sodium reacts completely according to the following reaction at 25oc and 1 atm?
22.7 liters approx volume of hydrogen gas is produced when 96.7 g of sodium reacts completely according to the following reaction at 25 degree C and 1 atm.
The chemical equation for the reaction is:
2Na(s) + 2H2O(l) -> 2NaOH(aq) + H2(g)
To calculate the volume of hydrogen gas produced, we first need to determine the number of moles of hydrogen produced. We can do this by using the molar mass of hydrogen and the mass of sodium that reacts. First, we convert the mass of sodium from grams to moles:
49.7 g Na / 22.99 g/mol = 2.17 mol Na
Since the chemical equation tells us that 2 mol of Na produce 1 mol of H2, we can use the mole ratio to calculate the number of moles of hydrogen produced:
2.17 mol Na * (1 mol H2 / 2 mol Na) = 1.09 mol H2
Next, we use the ideal gas law to calculate the volume of hydrogen gas produced at a temperature of 25 °C and a pressure of 1 atm:
V = (n * R * T) / P
where V is the volume of the gas, n is the number of moles, R is the gas constant, T is the temperature in Kelvin, and P is the pressure.
Putting values, we get:
V = (1.09 mol * 8.31 J/mol*K * 298 K) / 1 atm
= 22.7 L
So, the volume of hydrogen gas produced is approximately 22.7 liters.
It's important to note that this calculation assumes that the reaction goes to completion and that the hydrogen gas behaves as an ideal gas. In real-world situations, these assumptions may not always hold, so the actual volume of hydrogen gas produced may be different.
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Question - What volume of hydrogen gas is produced when 49.7 g of sodium reacts completely according to the following reaction at 25 °C and 1 atm?
2Na(s) + 2H2O(l) -> 2NaOH(aq) + H2(g)
how many moles of agcl(s) would form when 100. ml of 0.400 m agno3 is mixed with 90.0 ml of 0.250 m cacl2 ? g
100ml of 0.400 m AgNO3 and 90.0 ml of 0.250 m CaCl2 would combine to create 0.0225 moles of AgCl(s).
AgNO3 + CaCl2 -> AgCl + Ca(NO3)2 is the result of the given reaction
One mole of AgNO3 interacts with one mole of CaCl2 to produce one mole of AgCl in this reaction.
Given that AgNO3 (v1) has a volume of= 100 ml
Volume of CaCl2(v2) = 90ml
molarity of AgNO3 (m1) = 0.400M
Molarity of CaCl2 (m2) = 0.250M
Moles of AgNO3 formed: v1 x m1/1L = 0.1 x 0.4/1 = 0.04
moles of CaCl2 formed: v2 x m2/1L = 0.09 x 0.25/1L = 0.0225
Since AgNO3 exceeds 0.0225 moles of AgCl, CaCl2 is the limiting reactant in this limiting reactant problem.
Hence the number of moles of AgCl formed = 0.0225
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What is the percent compositions for nature's mix of lithium isotopes? What do you notice about the average atomic mass compare to the mass numbers for these same lithium isotopes? How does this relate back to how the average atomic mass is calculated?
The percent compositions for the naturally occurring isotopes of lithium are as follows: lithium-6 (7.5%), lithium-7 (92.5%), and lithium-8 (0.01%). The average atomic mass of lithium is calculated by taking into account the masses of all of its naturally occurring isotopes and the percent abundance of each isotope. When we look at the average atomic mass of lithium and compare it to the mass numbers of its isotopes, we can see that the average atomic mass is not equal to any of the individual isotope mass numbers. This is because the average atomic mass is a weighted average that takes into account the percent abundance of each isotope. Therefore, the average atomic mass of lithium is not the same as the mass number of any of its individual isotopes.
A food item that is left out of the refrigerator turns brown and forms bubbles and gas. What are the signs that this is a chemical reaction? check all that apply.
There are bubbles and the colour shifts.
what is chemical reaction?
A chemical reaction is defined as a process in which the chemical composition of a substance changes. A whole new chemical is created as a result of these reactions.
A chemical change would be the oxidation of iron to ferric oxide.
Here, iron that initially seems grey transforms to green before turning brownish red.
1. alteration in color
2. heat is gained or lost.
3.Gas evolution
4. precipitate formation these are some features of chemical reaction.
Therefore, when food that has been kept out of the refrigerator changes color and gas evolution occurs, there has been a chemical alteration.
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starting with a 1.35 m hcl stock solution, five standard solutions are prepared by sequentially diluting 5.00 ml of each solution to 100.0 ml. what is the concentration of the final solution?
Starting with a 1.35 m HCl stock solution, five standard solutions are prepared by sequentially diluting 5.00 ml of each solution to 100.0 ml. The concentration of the final solution after 5 dilutions is [tex]\rm 4.22 \times 10^{-7} M[/tex].
Dilution in chemistry is the process of lowering a solute's concentration in a solution by incorporating more solvent. Dilution is the process of lowering the solute concentration per unit volume while maintaining a constant solute concentration overall. As a result, the fluid becomes less concentrated or more diluted.
Volume of Stock Solution = 5 mL
= (5 mL)(1 L/1000 mL)
= 0.005 L
Moles of HCl = (1.35 mol/L)(0.005 L)
= [tex]\rm 6.75 \times 10^{-3}[/tex] mol
Dilution 1:-
Volume of Solution = 100 mL
= (100 mL)(1 L/1000 mL)
= 0.100 L
Molarity After 1st Dilution = ([tex]\rm 6.75 \times 10^{-3}[/tex] mol)/(0.100 L)
= [tex]\rm 6.75 \times 10^{-2}[/tex] mol/L
Volume of Solution Taken = 5 mL
= (5 mL)(1 L/1000 mL)
= 0.005 L
Moles of HCl = ([tex]\rm 6.75 \times 10^{-4 }[/tex]mol/L)(0.005 L)
=[tex]\rm 3.375 \times 10^{-4}[/tex] mol
Dilution 2:-
Volume of Solution = 100 mL
= (100 mL)(1 L/1000 mL)
= 0.100 L
Molarity After 2nd Dilution = ([tex]\rm 3.375 \times 10^{-4 }[/tex]mol)/(0.100 L)
=[tex]\rm 3.375 \times 10^{-3}[/tex] mol/L
Volume of Solution Taken = 5 mL
= (5 mL)(1 L/1000 mL)
= 0.005 L
Moles of HCl = ([tex]\rm 3.375 \times 10^{-3}[/tex] mol/L)(0.005 L)
= [tex]\rm 1.6875 \times 10-5[/tex] mol
Dilution 3:-
Volume of Solution = 100 mL
= (100 mL)(1 L/1000 mL)
= 0.100 L
Molarity After 3rd Dilution = ([tex]\rm1.6875 \times 10^{-5 }[/tex]mol)/(0.100 L)
= [tex]\rm 1.6875 \times 10^{-4}[/tex] mol/L
Volume of Solution Taken = 5 mL
= (5 mL)(1 L/1000 mL)
= 0.005 L
Moles of HCl = ([tex]\rm 1.6875 \times 10^{-4}[/tex] mol/L)(0.005 L)
= [tex]\rm 8.4375 \times 10^{-7}[/tex] mol
Dilution 4:-
Volume of Solution = 100 mL
= (100 mL)(1 L/1000 mL)
= 0.100 L
Molarity After 4th Dilution = ([tex]\rm 8.4375 \times 10^{-7 }[/tex]mol)/(0.100 L)
=[tex]\rm 8.4375 \times 10^{-6}[/tex] mol/L
Volume of Solution Taken = 5 mL
= (5 mL)(1 L/1000 mL)
= 0.005 L
Moles of HCl = ([tex]\rm 8.4375 \times 10^{-6 }[/tex]mol/L)(0.005 L)
= [tex]\rm 4.21875 \times 10^{-8}[/tex] mol
Dilution 5:-
Volume of Solution = 100 mL
= (100 mL)(1 L/1000 mL)
= 0.100 L
Molarity After 5th Dilution = ([tex]\rm 4.21875 \times 10^{-8}[/tex] mol)/(0.100 L)
=[tex]\rm 4.21875 \times 10^{-7}[/tex] mol/L
= [tex]\rm 4.22 \times 10^{-7}[/tex] mol/L
=[tex]\rm 4.22 \times 10^{-7}[/tex] M
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carbon disulfide has a vapor pressure of 363 torr at 25 degrees and a normal boiling point of 46.3 degrees find the change in hvap
The change in enthalpy of vaporization is 27.4 kJ/mol that can be calculated using Clausius-Clapeyron relation.
The Clausius-Clapeyron relation is used to characterize a discontinuous phase transition between two phases of the same constituent such as ice. The plot is drawn between 1/T vs ln P.
T1= 25+273=298 K
P1=363 Torr
T2= 46.3+273 = 319.3 K
P2= 760 Torr which is the atmospheric pressure.
By using the Clausius-Clapeyron equation,
ln(P2/P1)=ΔH/R[1/T1-1/T2]
ln (760/363)=ΔH/8.314x10^-3[1/298-1/319.3]
ΔH=27.44 kJ/mol
Therefore, the change in enthalpy of vaporization is 27.4 kJ/mol.
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The fuel used to power the booster rockets on space shuttles is a mixture of aluminum metal and ammonium perchlorate. the following balanced equation represents the reaction. 3al + 3nh4clo4 → al2o3 + alcl3 + 3no + 6h2o what is the mole ratio of al to al2o3?al:al2o3 = 3:
Answer: Al:Al2O3 = 3: 1
Explanation:
the answer is 1
You measured the pH of 2 solutions, a 0.1M HCl solution and a 0.1M acetic acid solution. Which of the following would be true?
1) The pH of the HCl is higher and the [H30+] is lower
2) The pH of the HCl is higher and the [H30+] is higher
3) The pH of the HCl is lower and the [H30+] is higher
4) The pH of the HCl is lower and the [H30+] is lower
5) The pH and [H30+] for the 2 solutions are the same
The pH of 2 solutions, a 0.1M HCl solution and a 0.1M acetic acid solution. The pH of the HCl is lower and the [H30+] is higher is true. Therefore, option 3 is correct.
What is pH ?The pH scale determines how acidic or basic water is. The range is 0 to 14, with 7 representing neutrality. Acidity is indicated by pH values below 7, whereas baseness is shown by pH values above 7. In reality, pH is a measurement of the proportion of free hydrogen and hydroxyl ions in water.
The pH scale, which previously stood for "potential of hydrogen," is used to describe how acidic or basic an aqueous solution is. The pH values of acidic solutions are typically lower than those of basic or alkaline solutions.
Thus, option 3 is correct.
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