Answer:
[tex]\%m/m=14\%[/tex]
Explanation:
Hello!
In this case, since the molarity of magnesium chloride (molar mass = 95.211 g/mol) is 1.672 mol/L and we know the density of the solution, we can first compute the concentration in g/L as shown below:
[tex][MgCl_2]=1.672\frac{molMgCl_2}{L}*\frac{95.211gMgCl_2}{1molMgCl_2}=159.2\frac{gMgCl_2}{L}[/tex]
Next, since the density of the solution is 1.137 g/mL, we can compute the concentration in g/g as shown below:
[tex][MgCl_2]=159.2\frac{gMgCl_2}{L}*\frac{1L}{1000mL}*\frac{1mL}{1.137g}=0.14[/tex]
Which is also the by-mass fraction and in percent it turns out:
[tex]\%m/m=0.14*100\%\\\\\%m/m=14\%[/tex]
Best regards!
For a particular reaction, the change in enthalpy is â9kJmole and the activation energy is 13kJmole. The enthalpy change (ÎH) and activation energy (Ea) for the catalyzed reaction could be which of the following? a. â9kJmole,5kJmole. b. â9kJmole,19kJmole.c. â14kJmole,5kJmole.d. â14kJmole,â13kJmole.
Answer:
The answer is Option a, that is "−9kJmole,5kJmole".
Explanation:
Please find the complete question in the attached file.
In the question, it uses the catalyst inside a process, which does not modify the process eigenvalues, however, it decreases the active energy with an enthalpy of -9kJmole, and also the power for activating decreases around 13 to 5 kJ mole, that's why the choice a is correct.
Which reason best explains why metals are malleable
Because they have delocalized electrons
Because they have localized electrons
Because they have ionic bonds
Because they have rigid bonds
Answer:
A.) because they have delocalized electrons
Explanation:
This is right on edg. 2020
Answer:
Bruzaaubrey is 100% correct
Explanation:
the proper answer is: "Because they have delocalized electrons(A)"Make sure to mark bruzaaubrey brainliest :)
what is the mass of silver that has a volume of 238mL? the density of silver is 10.5 g/cm^2
Explanation:
What volume of silver metal will weigh exactly 2500.0 g. The density of silver is 10.5 g/cm3. cm3 = 2500.0 g / 10.5 g/cm3 = 238 cm3
What is the density of a piece of wood that has a mass of 25.0 grams and a volume of 29.4 cm3? d = .85 g/cm3
Choose the most correct statement from the options below. Be sure to consult the
periodic table.
Magnesium (Mg) and chlorine (Cl) are in the same GROUP and, so, share
SIMILAR physical and chemical properties.
Magnesium (Mg) and chlorine (CI) are in the same PERIOD and, so, share
SIMILAR physical and chemical properties.
Magnesium (Mg) and chlorine (CI) are in the same PERIOD and, so, will have
very DIFFERENT physical and chemical properties.
Magnesium (Mg) and chlorine (CI) are in the same GROUP and, so, share
DIFFERENT physical and chemical properties.
Answer: B
Explanation:
Mg and Cl are in the same row aka period. Elements in the same period have similar properties like electron shells so the second option is the best answer
Suppose in an experiment to determine the amount of sodium hypochlorite in bleach, 0.0000538 mo KIO3 were titrated with an unknown solution of Na2S2O3 and the endpoint was reached after 17.80 mL. How many moles of Na2S2O3 did this require?
Answer:
3.228x10⁻⁴ moles of Na2S2O3 are required
Explanation:
In iodometry, the reaction of KIO3 with Na2S2O3 is:
KIO3 + 6 Na2S2O3 + 6H⁺ → KI + 3Na2S4O6 + 3H2O + 6Na⁺
Where 6 moles of Na2S2O3 reacts per moles of KIO3.
The moles of Na2S2O3 required to reach endpoint when 0.0000538 moles of KIO3 are:
0.0000538 moles of KIO3 * (6 moles Na2S2O3 / 1 mol KIO3) =
3.228x10⁻⁴ moles of Na2S2O3 are requiredif a student added water to her cola what change would you expect to see in the ph level
Answer:
You would expect it to go down
Explanation:
This is because she is essentially watering down, causing the Ph level to go down too.
If a student added water to her cola, then the pH level is low. This is due to the fact that she is essentially diluting, which lowers the pH level as well.
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.
pH stands for "Potential of Hydrogen" in its full form. The negative logarithm of the concentration of H+ ions is known as pH. As a result, the meaning of pH is defined as the strength or power of hydrogen.
A solution's pH is a significant indicator of its chemical composition. The pH can affect how readily available nutrients are, how biological processes work, how bacteria behave, and how chemicals behave.
Thus, If a student added water to her cola, then the pH level is low.
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How is thermal energy transferred during conduction? Check all that apply.
Thermal energy is transferred hetween particles that are not touching each other.
Thermal energy is transferred between particles that are in direct contact with each other.
Thermal energy is transferred between objects of different temperatures.
Thermal energy is transferred between objects of the same temperature.
Thermal energy is transferred from slow-moving particles to fast-moving particles.
Thermal energy is transferred from fast-moving particles to slow-moving particles.
Answer:energy
Explanation:needed points sorry
How does one determine a percent composition from an empirical
formula?
A. Divide the atomic mass of the element by its subscript and
multiply by 100%
O B. Divide the mass of the compound by the atomic mass of
the element and multiply by 100%
O C. Divide the subscript of the element by the mass of the
element and multiply by 100%
O D. Divide the total mass of each element by the mass of the
compound and multiply by 100%
The way one determines a percent composition from an empirical formula is to divide the total mass of each element by the mass of the compound and multiply by 100%.
What is empirical formula?Empirical formula is a notation that indicates the ratios of the various elements present in a compound, without regard to the actual numbers.
The empirical formula of a compound is the simplest ratio that can exist between the constituent elements of a compound.
However, the percent composition of a compound can be determined by dividing the total mass of each element by the mass of the compound and multiply by 100%.
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A 1.038 g sample of unknown containing C, H, and O yielded 2.48 g of CO2 and 0.510 g of H2O during combustion analysis. Determine the empirical formula of the compound.
A) C3H3O
B) C6H6O
C) CH3O
D) C6H6O2
E) C2H6O2
Answer:
A. C3H3O
Explanation:
We have the following data:
m = mass of organic compound = 1.038g
Then mass of CO2 is 2.48g
Also mass of H2O is 0.510g
To calculate percentage of carbon = 12 x mass of CO2 x 100/44 x mass of organic compound
This gives us 65.1 percent
Formula to calculate percentage of H=
2 x mass of water x 100/18 x mass of organic compound.
= 2 x 0.510 x 100/18x 10038
This gives 5.4%
Percentage of Oxygen =100-(percentageof carbon +percentageof H)
= 100-(65.1+5.4)
= 100-70.5
= 29.5
We have to calculate emperical formula:
For C = 65.1
65.1/12
= 5.4
= 5.4/1.8
=3
For H=5.4
5.4/1
= 5.4
= 5.4/1.8
=3
For O = 29.5
= 29.5/16
= 1.8
= 1.8/1.8
=1
So the emperical formula of organic compound is given as
C3H3O1
= C3H3O
(The atomic weights of C, H, O are 12,1,16)
What is the energy of a wave if the frequency is 300. Hz
Answer:
[tex]E=1.98\times 10^{-31}\ J[/tex]
Explanation:
Given that,
The frequency of a wave, f = 300 Hz
We need to find the energy of a wave. The formula for the energy of a wave is given by :
E = hf,
Where h is Planck's constant
[tex]E=6.63\times 10^{-34}\times 300\\\\=1.98\times 10^{-31}\ J[/tex]
So, the energy of the wave is [tex]1.98\times 10^{-31}\ J[/tex].
For the reaction of nitric oxide and oxygen to form nitrogen dioxide, the reaction begins with 12.0 g of nitric oxide and 12.0 g of oxygen at 25oC in a 10.0 L container. At equilibrium, the pressure in the container is 1148 mmHg, what is Kp?
Answer:
Explanation:
Hello!
In this case, since the undergoing chemical reaction is:
[tex]2NO+O_2\rightleftharpoons 2NO_2[/tex]
The equilibrium expression in terms of pressures is:
[tex]Kp=\frac{p_{NO_2}^2}{p_{NO}^2p_{O_2}}[/tex]
Thus, for the initial conditions, we compute the initial pressures of both nitric oxide and oxygen:
[tex]p_{NO}^{0}=\frac{12.0g*0.082\frac{atm*L}{mol*K}*298.15K}{30g/mol*10.0L}=0.978atm\\\\ p_{O_2}^{0}=\frac{12.0g*0.082\frac{atm*L}{mol*K}*298.15K}{32g/mol*10.0L}=0.917atm[/tex]
Next, since the equilibrium pressure is 1148 mmHg or 1.51 atm, we can write:
[tex]p_T=p_{NO_2}+p_{NO}+p_{O_2}\\\\1.51=2x+0.978-2x+0.917-x\\\\1.51=1.90-x\\\\x=0.39atm[/tex]
Thus, the Kp turns out:
[tex]Kp=\frac{(2*0.39)^2}{(0.978-2*0.39)^2(0.917-x)} \\\\Kp=29.4[/tex]
Best regards!
The density of osmium (the densest metal) is 22.57 g/cm3.
What is the mass of a block of osmium with dimensions:
4.22 cm x 3.62 cm x 1.41 cm?
Answer: mass = 485 grams approximately
=======================================================
Work Shown:
First we need the volume of the block
volume = (length)*(width)*(height)
volume = (4.22)*(3.62)*(1.41)
volume = 21.539724
volume = 21.5 cubic cm
I'm rounding to three sig figs because each of the dimensions are to three sig figs.
--------------------------
Now turn to the formula
density = mass/volume
This can be rearranged to
mass = density*volume
Plug in the given density and the volume we found earlier to get
mass = density*volume
mass = (22.57)*(21.5)
mass = 485.255
mass = 485 grams
I'm rounding to three sig figs because it's the smaller sig fig count of 22.57 and 21.5
A strong electrolyte is one that ________ completely in solution. a) reacts.b) decomposes.c) disappears.d) ionizes.
Answer:
A.
Explanation:
elctrolytes decomposes
Answer:
D. ionizes
Explanation:
Is SO3 ionic or ionic using the stock system or molecular
Answer:
Molecular
Explanation:
Using the rules for the nomenclature for naming binary covalent (molecular) compounds, the compound SO3 is named sulfur trioxide. The prefix tri- indicates that the oxygen has a subscript of 3 and that a molecule of sulfur trioxide has three oxygen atoms.
Identify the titration curve for a monoprotic weak acid titrated with a strong base.
Answer:
Titration is a technique to determine the concentration of an unknown solution. As illustrated in the titration setup above, a solution of known concentration (titrant) is used to determine the concentration of an unknown solution (titrand or analyte).
Typically, the titrant (the solution of known concentration) is added through a burette to a known volume of the analyte (the solution of unknown concentration) until the reaction is complete. Knowing the volume of titrant added allows us to determine the concentration of the unknown analyte. Often, an indicator is used to signal the end of the reaction, the endpoint. Titrant and analyte is a pair of acid and base. Acid-base titrations are monitored by the change of pH as titration progresses.
Let us be clear about some terminologies before we get into the discussion of titration curves.
Convert 98.5 Pa into mm Hg. (133.32 Pa = 1.00 mm Hg)
Which letter indicates the asthenosphere
Answer:
q
Explanation:
PLS HELP ME FOR BOTH QUESTIONS
Answer:
IF the match is stuck on the side it could chach burning hot.
2) the burn peices looks like its burned and it becomes black since of it.
Explanation:
What effect does a high carbon level have on the deep ocean? Why might it be important to keep an eye on the deep ocean carbon levels? What could that one number tell you about the cycle as a whole?
High concentrations of carbon dioxide make it harder for marine animals to respire (to extract oxygen from seawater). This, in turn, makes it harder for these animals to find food, avoid predators, and reproduce. Low concentrations of oxygen can have similar effect
Becay the Ocean's Carbon Balance. The idea seemed simple enough: the more carbon dioxide that people pumped into the atmosphere by burning fossil fuels, the more the oceans would absorb. ... Water trapped at the surface would become saturated, at which point, the ocean would slow its carbon uptake.
Which one is NOT true about chemical changes? *
Answer:
The second answer
Explanation:
Phase changes is an example of physical change because it only changes the substance's appearance.
Answer: 1 and 4 are the answers
Explanation: because when you mix a sub since and it will have a chemical change
What is the difference between homogeneous and heterogeneous mixtures?
Maybe someone knows how to name compounds by IUPAC ?
Explanation:
The IUPAC system of nomenclature aims to ensure
that every organic compound has a unique, unambiguous name.that the IUPAC name of any compound conveys the structure of that compound to a person familiar with the system.
One way of checking whether the name you have given to an alkane is reasonable is to count the number of carbon atoms implied by the chosen name. For example, if you named a compound 3‑ethyl-4‑methylheptane, you have indicated that the compound contains a total of 10 carbon atoms—seven carbon atoms in the main chain, two carbon atoms in an ethyl group, and one carbon atom in a methyl group. If you were to check the given structure and find 11 carbon atoms, you would know that you had made a mistake. Perhaps the name you should have written was 3‑ethyl-4,4‑dimethylheptane!
Which numerical setup can be used to calculate the
atomic mass of the element bromine?
Answer:
From the numerical steps highlighted under explanation, the average atomic mass of bromine is 79.91 u
Explanation:
The steps to be taken will involve;
1) Find the number of isotopes of bromine.
2) Identify the atomic mass and relative abundance of each of the isotopes.
3) Multiply the atomic mass of each of the isotopes by their corresponding values relative abundance value.
4) Add the value in step 3 above to get the average atomic mass of bromine.
Now;
Bromine has 2 isotopes namely;
Isotope 1: Atomic mass = 78.92amu and a relative abundance of 50.69%.
Isotope 2: Atomic mass = 80.92amu and a relative abundance of 49.31%.
Using step 3 above, we have;
(78.92 × 50.69%)
And (80.92 × 49.31%)
Using step 4 above, we have;
(78.92 × 50.69%) + (80.92 × 49.31%) ≈ 79.91 u
The atomic mass of bromine has been calculated as 79.9062 amu.
The relative atomic mass of the element has been given as the mass of each isotope with respect to their abundance.
The atomic mass has been given as:
[tex]amu=\sum mass\;\times\;\% Abundance[/tex]
The available isotopes of Bromine have been:
Isotope 1 = 78.92 amu, and 0.5069 % abundance
Isotope 2= 80.92 amu, and 0.4931 % abundance
Submitting the values for the atomic mass unit of bromine ([tex]amu_{\text{Br}}[/tex]):
[tex]amu_{\text {Br}}= (78.92\;\times\;0.5069)\;+\;(80.92\;\times\;0.4931)\\amu_{\text{Br}}=40.0045\;+\;39.9016\\amu_{\text{Br}}=79.9062[/tex]
The atomic mass of bromine has been calculated as 79.9062 amu.
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Please help on the image below.
Heat capacity of Calorimeter = 10.7 J/°c
Further explanationHeat lost=Heat gained
Q in = Q out
-Q lost(hot water)=Q gained (cold water+calorimeter)
-m.c.Δt=m.c.Δt+C.Δt
[tex]\tt \rightarrow -50\times 4.18\times (32.7-43)=50\times 4.18\times (32.7-22.9)+(32.7-22.9)\times C_{cal}\\\\\rightarrow 2152.7=2048.2+9.8\times C_{cal}\\\\104.5~J=9.8\times C_{cal}\\\\C_{cal}=\dfrac{104.5}{9.8}=10.7~J/^oC[/tex]
Identify the molecule with the strongest intermolecular force.
C6H6
OF2
CHCl3
H2O
Answer:
C6H6 has the strongest intermolecular force
i think
Answer:
H2O
Explanation:
Because it is a hydrogen bond which is said to be the strongest bond between the H and a N,O, or F combination
How many kilpgrams are in 2.71x10^22 molecules of CO2
Answer:
mass of 1 molecule of CO2=44 g
mass of 2.71*10^22 of CO2=2.71*10^22*44=1.2*10^24g
now to convert grams into kilogram we know that
1000 g=1kg
1.2*10^24=1.2*10^24/1000=1.2*10^21
According to Avogadro's number concept,there are 1.979×10[tex]^-3[/tex] kilograms in 2.71 ×10²² molecules of CO₂.
What is Avogadro's number?Avogadro's number is defined as a proportionality factor which relates number of constituent particles with the amount of substance which is present in the sample.
It has a SI unit of reciprocal mole whose numeric value is expressed in reciprocal mole which is a dimensionless number and is called as Avogadro's constant.It relates the volume of a substance with it's average volume occupied by one of it's particles .
According to the definitions, Avogadro's number depend on determined value of mass of one atom of those elements.It bridges the gap between macroscopic and microscopic world by relating amount of substance with number of particles.
Number of atoms can be calculated using Avogadro's number as follows: mass/molar mass×Avogadro's number. Mass is calculated as, number of molecules/Avogadro's number×molar mass
Substitution in above formula gives, mass=2.71×10²²/6.023×10²³×44=1.979 g or 1.979×10[tex]^-3[/tex] kg.
Thus, there are 1.979×10[tex]^-3[/tex] kg in 2.71×10²² molecules of carbon dioxide.
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what is molecular weight of ash?
Answer:
AsH(2.) CHEBI:33104
Explanation:
Molecular Weight is : 75.9296 g/mol
plz answer plzplzpzlpl
Which statement is not true for a magnetic field?
O A. A magnetic field occurs near a wire that has no current.
OB. A magnetic field is produced by a magnet with two poles.
O c. A magnetic field loops from the north pole to the south pole.
O D. A magnetic field occurs near a current-carrying wire.
Answer:
The answer is letter A.
A. A magnetic field occurs near a wire that has no current.
Because magnetic field occur near a current carrying wire.
A 32.65 g metal is placed in a flask. Liquid toluene is added to the flask so that the total volume of the metal and liquid toluene together is 50.00 mL. The metal and toluene together weigh 58.58 g. The density of toluene at the temperature of the experiment is 0.8640 g/mL. What is the density of the metal?