Answer:
747.5 mL
Explanation:
Assuming ideal behaviour, we can solve this problem by using Boyle's law, which states that at constant temperature:
P₁V₁ = P₂V₂Where in this case:
P₁ = 681 mm HgV₁ = ?P₂ = 991 mm HgV₂ = 513.7 mLWe input the data given by the problem:
681 mm Hg * V₁ = 991 mm Hg * 513.7 mLAnd solve for V₁:
V₁ = 747.5 mLI need help solving this!
For the reaction C + 2H2 → CH4, how many moles of hydrogen are needed to make 146.6 grams of methane, CH4 ?
Round your answer to the nearest tenth. If you answer is a whole number like 4, report the answer as 4.0
Use the following molar masses. If you do not use these masses, the computer will mark your answer incorrect.:
Element
Molar Mass
Hydrogen
1
Carbon
12
Answer: Moles of hydrogen required are 4.57 moles to make 146.6 grams of methane, [tex]CH_{4}[/tex].
Explanation:
Given: Mass of methane = 146.6 g
As moles is the mass of a substance divided by its molar mass. So, moles of methane (molar mass = 16.04 g/mol) are calculated as follows.
[tex]Moles = \frac{mass}{molar mass}\\= \frac{146.6 g}{16.04 g/mol}\\= 9.14 mol[/tex]
The given reaction equation is as follows.
[tex]C + 2H_{2} \rightarrow CH_{4}[/tex]
This shows that 2 moles of hydrogen gives 1 mole of methane. Hence, moles of hydrogen required to form 9.14 moles of methane is as follows.
[tex]Moles of H_{2} = \frac{9.14}{2}\\= 4.57 mol[/tex]
Thus, we can conclude that moles of hydrogen required are 4.57 moles to make 146.6 grams of methane, [tex]CH_{4}[/tex].
The following statements either define or are closely related to the terms periodic law, period, or group. Match the terms to the appropriate statements.1. This is a vertical arrangement of elements in the periodic table. 2. This is a horizontal arrangement of elements in the periodic table. 3. The properties of the elements repeat in a regular way as the atomic numbers increase. 4. Element 19 begins this arrangement in the periodic table 5. The chemical properties of elements 12, 20, and 38 demonstrate this principle.
Answer:
Please find the complete solution in attached file.
Explanation:
Periodic law is the the properties of the elements that repeat in a regular way as the atomic numbers increase.
What is periodic table?Periodic chart organized collection of all chemical elements arranged roughly according to increasing atomic weight. The periodic recurrence of several features in the elements was originally identified by Dmitry I. Mendeleyev in 1869.
1. This is a vertical arrangement of elements in the periodic table group
2. This is a horizontal arrangement of elements in the periodic table period
3. The properties of the elements repeat in a regular way as the atomic numbers increase periodic law
4. Element 19 begins this arrangement in the periodic table period
5. The chemical properties of elements 12, 20, and 38 demonstrate this principle. periodic law
Therefore, periodic law is the the properties of the elements that repeat in a regular way as the atomic numbers increase.
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Give the name of the molecular compound and the name of the aqueous solution for each of the binary compounds below.
a. HCN
b. HF
c. H2S
Explanation:
A compound containing only two elements is called a binary compound.
(a). The compound HCN contains a hydrogen ion and cyanide ion. Hence, the name of HCN is hydrogen cyanide.
An aqueous solution of hydrogen cyanide is known as hydrogen cyanide solution.
(b). The compound HF contains a hydrogen ion and a fluorine ion. The suffix -ide will be added to its name. So, the name of this compound is hydrogen fluoride.
An aqueous solution of HF is known as hydrogen fluoride.
(c). The compound [tex]H_{2}S[/tex] contains two hydrogen atoms and one sulfur atom. The suffix -ide will be added to its name. So, the name of this compound is hydrogen sulfide.
An aqueous solution of this compound is known as hydrogen sulfide solution.
The titration of a weak acid with a strong base is a common exercise in chemistry labs. We have looked at all of the individual types of calculations needed to determine the pH at any point of a titration. Consider the titration of 0.100 L of 0.300 M acetic acid with 2.00 M NaOH. What type of calculation will we be performing at the following points of the titration curve
Answer:
1. Weak acid calculation
2. Strong base calculation
3. Strong base calculation
4. Strong base calculation
Explanation:
1. Zero equivalents of base added
2. 0.15 equivalents of base added
3. One equivalent of base added
4. 1.75 equivalents of base added
The equivalents of acetic acid are:
0.100L * (0.300mol/L) = 0.0300 moles of acetic acid = 0.0300Eq.
1. With Zero equivalents of base added you will calculate pH using weak acid calculation because you have only acetic acid (Weak acid) in the solution.
2. When 0.15 equivalents of base are added all the acid reacted and 0.15-0.03 = 0.12 equivalents of Strong base are in excess. With these equivalents and the volume we can find pH using strong base calculation.
3 and 4. As with 0.15 eq. added the 1 eq. and 1.75 eq. produce an excess of strong base and the pH must be calculated by using strong base calculation
The main importance of the titration curve is that it is used show how the pH of the solution changes as a titrant is added to the solution.
What is a titration curve?A titration curve is a plot of pH of the system against the volume of titrant added. The question is incomplete but I will try to explain what a titration curve is.
The main importance of the titration curve is that it is used show how the pH of the solution changes as a titrant is added to the solution.
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4.106
Calculate the moles and the mass of solute in each of the following solutions.
(a) 150.0 mL of 0.245 M CaCl2
molarity = moles of solute / volume of solution
moles of solute = molarity × volume of solution
moles of solute = 0.245 mol/L × 0.1500 L
moles of solute = 0.03675 mol
moles of solute = 0.0368 mol
-----------------------------------------------------------
Solution: (mass of solute)Step 1: Calculate the molar mass of solute.
molar mass of solute = (40.08 g/mol × 1) + (35.45 g/mol × 2)
molar mass of solute = 110.98 g/mol
Step 2: Calculate the mass of solute.
mass of solute = moles of solute × molar mass of solute
mass of solute = 0.03675 mol × 110.98 g/mol
mass of solute = 4.08 g
Note: The volume of solution must be expressed in liters (L).
Answer:
[tex]\boxed {\sf \bold {0.0368 \ mol \ CaCl_2}}}}[/tex]
[tex]\boxed {\sf \bold {4.08 \ g \ CaCl_2}}}}}[/tex]
Explanation:
1. Moles of SoluteMolarity is a measure of concentration in moles per liter.
[tex]molarity= \frac {moles \ of \ solute}{liters \ of \ solution}[/tex]
In this solution, there are 150.0 milliliters of solution and the molarity is 0.245 M CaCl₂ or 0.245 mol CaCl₂ per liter.
First, convert the milliliters to liters. There are 1000 milliliters in 1 liter.
[tex]{150 \ mL * \frac{1 \ L}{1000 \ mL}= \frac{150}{1000} \ L = 0.150 \ L[/tex]Now, substitute the known values (molarity and liters of solution) into the formula. The moles of solution are unknown, so we can use x.
[tex]0.245 \ mol \ CaCl_2 /L= \frac{ x}{0.150 \ L}[/tex]
We are solving for x, so we must isolate this variable. It is being divided by 0.150 L. The inverse of divisions is multiplication, so we multiply both sides by 0.150 L.
[tex]0.150 \ L *0.245 \ mol \ CaCl_2 /L= \frac{ x}{0.150 \ L} * 0.150 L[/tex]
[tex]0.150 \ L *0.245 \ mol \ CaCl_2 /L=x[/tex]
The units of liters cancel.
[tex]0.150 *0.245 \ mol \ CaCl_2 =x[/tex]
[tex]0.03675 \ mol \ CaCl_2[/tex]
The original measurements have 3 significant figures, so our answer must have the same.
We should round to the ten thousandths place. The 5 to the right of this place tells us to round the 7 up to an 8.
[tex]\bold {0.0368 \ mol \ CaCl_2}[/tex]
2. Mass of the SoluteWe can convert mass to moles using the molar mass. These values are found on the Periodic Table. They are the same as the atomic masses, but the units are grams per mole (g/mol) instead of atomic mass units.
The solute is calcium chloride: CaCl₂. Look up the molar masses of the individual elements.
Ca: 40.08 g/mol Cl: 35.45 g/molNotice that chlorine has a subscript of 2. We must multiply the molar mass by 2.
Cl₂: 35.45 *2= 70.9 g/molAdd calcium's molar mass.
CaCl₂: 40.08 + 70.9 =110.98 g/molUse the molar mass as a ratio.
[tex]\frac {110.98 \ g\ CaCL_2}{ 1 \ mol \ CaCl_2}[/tex]
Multiply the moles of calcium chloride we calculated above.
[tex]0.0368 \ mol \ CaCl_2 *\frac {110.98 \ g\ CaCL_2}{ 1 \ mol \ CaCl_2}[/tex]
The units of moles of calcium chloride cancel.
[tex]0.0368 *\frac {110.98 \ g\ CaCL_2}{ 1 }[/tex]
[tex]4.084064 \ g\ CaCl_2[/tex]
Round to 3 significant figures again. For this number, it is the hundredths place. The 4 in the thousandths place tells us to leave the 8.
[tex]\bold {4.08 \ g \ CaCl_2}[/tex]
Increasing the temperature of a chemical reaction usually increases greatly the rate of the reaction. The most iportant reason for this is that increasing the temperature increases: _______.
A) the collision frequency
B) the probability factor
C) the fraction of collisions with energy greater than Bact
D) the energy of activation.
E) the amount of heat released in the reaction
Answer:
the fraction of collisions with energy greater than Eact
Explanation:
The activation energy of a reaction stands as a sort of energy barrier between reactants and products. It is only reactants that possesses energy greater than the activation energy that can be converted from reactants to products.
When the temperature of the system is increased, more particles acquire energy greater than the activation energy. Hence, the fraction of collisions with energy greater than the activation energy increases so the rate of reaction increases likewise.
Which of the following can be determined from the frequency of a light wave?
O A. The height of the wave
O B. The direction of the wave
O C. The source of the wave
O D. The energy of the wave
I Am Thinking A.
Answer:
The answer is d because the light is energy of wave
The frequency of a light wave can be determined
The energy of the wave.So, option D is correct one.
What is frequency?
The number of occurrence of repeating events per unit time is called frequency.The units of frequency is per second or Hertz(Hz).The frequency is used to calculate energy of light .The frequency is directly proportional to the energy. So, if frequency increases the energy also increases.Energy equation,
[tex]E= hv[/tex]
where,
[tex]E[/tex] = Energy of light
[tex]h[/tex]= Planks constant
[tex]v[/tex] = Frequency of wave.
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How much cesium (half-life = 2 years) would remain from a 10 g sample after
6 years?
O A. 59
O B. 119
O c. 2 1 2
O D.09
Answer:
The correct answer is A. 59.
Explanation:
The formula for finding the amount of radio active substance that remains after decomposition is A = N(1/2) ^y, where A is the mass remaining, N is the original mass of a radioactive sample and y is the number of half life. In this case, N = 10 g and y = 6/2 = 3. So A is given by 10 x (1/2)^3, which is 10 x 1/2 x1/2 x 1/2 = 1.25 grams.
Plz help me ASAP in my final project I am ready to pay 20$
Excluding any secondary chemical reactions,
which would be more effective as an antifreeze; a
solution containing
Select one:
25m CH3OH
the combination of 25m CH3OH and 25m
KCI.
O 25m KCI.
O
none of these
Answer:
Excluding any secondary chemical reactions,
which would be more effective as an antifreeze; a
solution containing
Select one:
25m CH3OH
the combination of 25m CH3OH and 25m
KCI.
25m KCI.
Explanation:
Antifreeze is the one that reduces the freezing point of a solvent further and will not allow the solvent to freeze.
Among the given options, the correct option is:
25 m CH3OH and 25m KCl.
Since, KOH is a strong electrolyte and dissociates into two ions.
So, the freezing point of solvent decreases further.
The table shows the nature of reactants and products formed in a certain type of chemical reaction.
Nature of Reactants and Products
Reactants
Metal + lonic compound
Products
Metal + lonic compound
Which of the following is true about the type of chemical reaction?
it is a single replacement reaction, and the anions in the two inic compounds are different.
It is a single replacement reaction, and the cations in the two ionic compounds are different.
It is a double replacement reaction, and the anions in the two ionic compounds are different.
It is a double replacement reaction, and the cations in the two ionic compounds are different.
Answer: It is true about the type of reaction that it is a single replacement reaction, and the cations in the two ionic compounds are different.
Explanation:
When one element in a compound is replaced by another element in a chemical reaction then it is called a single replacement reaction.
For example, [tex]K + NaCl \rightarrow KCl + Na[/tex]
Here, potassium metal is replacing the sodium metal in the sodium chloride compound.
As metals become cation by losing an electron in a chemical reaction.
Thus, we can conclude that it is true about the type of reaction that it is a single replacement reaction, and the cations in the two ionic compounds are different.
Answer: Its A
Explanation:
a single replacement reactions, and the ANIONS in the two ionic compounds are different
You’re taking a walk on a warm fall morning. The temperature is about 70 degrees Fahrenheit, and you cannot see a cloud anywhere in the sky. You notice that the ground has no dew on it either. This means the
this means that you are wearing warm clothes in warm temperature .quite easy sir
The number of periods/series in Mendeleev's Periodic table is
A. 10
B. 13
C. 12
D. 14
Answer: The number of series in Mendeleev's Periodic table is 12.
Explanation:
Horizontal rows present in the periodic table are called periods. Vertical rows in the periodic table are called series.
Mendeleev gave periodic table in the year 1869 by arranging elements according to their atomic weights a in tabular form.
Mendeleev's periodic table depicts 12 periods/series.
Thus, we can conclude that the number of periods/series in Mendeleev's Periodic table is 12.
A calorimeter measures the ______ involved in reactions or other processes by measuring the ______ of the materials _____ in the process. The calorimeter is _______ to prevent transfer of heat to outside the device.
Answer:
heat; temperature; surrounding; insulated.
Explanation:
A calorimeter can be defined as a scientific instrument or device designed and developed for measuring the heat involved in reactions or other processes, especially by taking the measurement of the temperature of the materials surrounding the process.
Basically, a calorimeter is insulated using materials with very high level of resistivity so as to prevent heat transfer to the outside of the device (calorimeter). Some of the components that make up a simple calorimeter are thermometer, an interior styrofoam cup, an exterior styrofoam cup, cover, etc.
Additionally, a calorie refers to the amount of heat required to raise the temperature of a gram of water by one degree Celsius (°C).
On the basis of your knowledge of the reaction of halogens with alkanes, decide which product you would not expect to be formed in even small quantities in the bromination of ethane?
A) BrCH2CH2Br
B) CH3CH2CH2Br
C) CH3CHBr2
D) CH3CH2CH2CH3
E) BrCH2CH2CH2CH2Br
Answer:
On the basis of your knowledge of the reaction of halogens with alkanes, decide which product you would not expect to be formed in even small quantities in the bromination of ethane?
A) BrCH2CH2Br
B) CH3CH2CH2Br
C) CH3CHBr2
D) CH3CH2CH2CH3
E) BrCH2CH2CH2CH2Br
Explanation:
The reaction of ethane with bromine in presence of UV light forms mono substituted ethane at all primary and secondary carbons.
This is an example of free radical substitution.
The structure of ethane and its bromination is shown below:
Among the given options that which is not possible to form is option B) that is CH3CH2CH2Br(propyl bromide).
Remaining all other products are possisble to form on free radical substitution of ethane.
Identify the statements that correctly describe the saturation temperature of a solution.
A. Any temperature at which the solution is liquid.
B. Any temperature at which all of the compound is solid.
C. The temperature at which solid begins to appear from a cooled solution.
D. The temperature at which the Ksp value can be calculated.
Which gas has the greatest kinetic energy at STP?
H2, Ne, N2 or none
Answer:
none All have the same kinetic energy
Explanation:
Suppose an enzyme and its substrate obey the lock and key model of enzyme catalysis. Which of the following would be true of the enzyme?
a. only one substrate could be converted to product by the enzyme
b. the active site of the enzyme must be rigid
c. the entire enzyme must be rigid
d. the active site of the enzyme must be flexible
e. the enzyme could bind different substrates if the substrates shared a common motif somewhere in their structures
Answer:
only one substrate could be converted to product by the enzyme
Explanation:
If an enzyme obeys the lock and key model, it then follows that the design of the enzyme is unique to a particular substrate.
Just as only the correct key can effectively fit into a lock, only the appropriate substrate whose design matches that of the enzyme can fit into the enzyme.
Owing to the lock and key model of enzyme activity, only one enzyme could interact with a substrate to yield particular product.
How is stoichiometry used to calculate energy released when a mass of liquid freezes?
A. Grams liquid x mol/g x delta Hreaction
B. Grams liquid x mol/g x delta Hfusion
C. Grams liquid x mol/g x delta Hvap
D. Grams liquid x mol/g x delta Hf
The formula that we can use to calculate energy released when a mass of liquid freezes is Grams liquid x mol/g x delta Hfusion.
What is stoichiometry?Stoichiometry deals with the relationship between mass and moles or volume which can be used to make calculations involving chemical reactions. Most chemical calculations involving stoichiometry use the mole concept.
Hence, the formula used to obtain the energy released when a mass of liquid freezes is Grams liquid x mol/g x delta Hfusion.
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Does a reaction occur when aqueous solutions of copper(II) nitrate and calcium chloride are combined
Answer:
Does a reaction occur when aqueous solutions of copper(II) nitrate and calcium chloride are combined?
Explanation:
The given reaction is an example of a chemical double displacement reaction.
The mutual interchange of the ions takes place.
The balanced chemical equation of the reaction is:
[tex]Cu(NO_3)_2(aq)+CaCl_2(aq) -> Ca(NO_3)_2(aq)+CuCl_2(aq)[/tex]
All the products formed are also highly soluble.
So, all the ions are spectator ions.
Hence, all will cancel with each other and ions remain in the net ionic equation and hence, the reaction does not take place.
How many grams of O2 are needed to react with 8.15 g of C2H2?
Answer:
25.08 grams of O₂ are needed to react with 8.15 g of C₂H₂.
Explanation:
The balanced reaction is:
2 C₂H₂ + 5 O₂ → 4 CO₂ + 2 H₂O
By reaction stoichiometry, the following amounts of moles of each compound participate in the reaction:
C₂H₂: 2 molesO₂: 5 molesCO₂: 4 molesH₂O: 2 molesThe molar mass of each compound is:
C₂H₂: 26 g/moleO₂: 32 g/moleCO₂: 44 g/moleH₂O: 18 g/moleThen, by reaction stoichiometry, the following mass quantities of each compound participate in the reaction:
C₂H₂: 2 moles* 26 g/mole= 52 gO₂: 5 moles* 32 g/mole= 160 gCO₂: 4 moles* 44 g/mole= 176 gH₂O: 2 moles* 18 g/mole= 36 gThen you can apply the following rule of three: if by stoichiometry 52 grams of C₂H₂ react with 160 grams of O₂, 8.15 grams of C₂H₂ react with how much mass of O₂?
[tex]mass of O_{2} =\frac{8.15 grams of C_{2} H_{2}*160 grams of O_{2} }{52 grams of C_{2} H_{2}}[/tex]
mass of O₂= 25.08 grams
25.08 grams of O₂ are needed to react with 8.15 g of C₂H₂.
Select the statement that best answers the following question What effect does the anion of an ionic compound have on the appearance of the solution?
a. The anion affects the intensity of the color more than the color of the solution.
b. The anion affects the color of the solution more than the intensity of the color.
c. The anion does not affect the color or color intensity of the solution.
d. The anion only affects the intensity of the color in a solution.
Answer:
b. The anion affects the color of the solution more than the intensity of the color.
Explanation:
An ionic compound is one that is made up of ions held together by electrostatic forces. The ions are made up of positively charged ions known as cations and negatively charged ions known as anions. In compounds with a high ionic attribute, anions produce colorless compounds. But compounds that have less ionic attributes produce deeper colors like black and red. When in solutions, ionic compounds take on color and this is because of the anion that absorbs infrared light energy.
You are stowing items and come across an aerosol bottle of hairspray. What should you do? Please choose all that apply
Answer:stow the hairspray
Explanation:
The enthalpy of Sodium is 235 calories. The enthalpy Chlorine is 435 calories. The enthalpy of Sodium chloride 670 joules, what is the change in enthalpy for this reaction?
Answer:
ΔH = -2446J
Explanation:
Based on the reaction:
2 Na(s) + Cl2(g) → 2NaCl
We can find the enthalpy of this reaction using Hess's law:
The enthalpy of a reaction is equal to the sum of the enthalpy of products times their reaction quotient subtracting the enthalpy of reactants times their reaction quotient. For the reaction of the problem:
ΔH = 2ΔH(NaCl) - [2ΔH(Na) + ΔHCl2)]
ΔH(NaCl) = 670J
ΔH(Na) = 235cal * (4.184J/1cal) = 983J
ΔHCl2 = 435cal * (4.184J/1cal) = 1820J
ΔH = 2*670J - [2*983J + 1820J]
ΔH = 1340J - [3786J]
ΔH = -2446JAnswer:
the heat content of a system at constant pressure
Explanation:
The element antimony has two stable isotopes, antimony-121 with a mass of 120.90 amu and antimony-123 with a mass of 122.90 amu. From the atomic weight of Sb = 121.76 one can conclude that: ________
antimony-123 has the highest percent natural abundance
most antimony atoms have a mass of 121.76 amu
antimony-121 has the highest percent natural abundance
both isotopes have the same percent natural abundance
Answer:
antimony-121 has the highest percent natural abundance
Explanation:
percent natural abundance;
121.76 = 120.90 x + 122.90 (1 - x)
121.76 = 120.90 x + 122.90 - 122.90x
121.76 = -2x + 122.90
121.76 - 122.90 = -2x
x= 121.76 - 122.90/ -2
x= 0.57
Where x and 1 - x refers to the relative abundance of each of the isotopes
Percent natural abundance of antimony-121 = 57 %
Percent natural abundance of antimony-123 = (1 - 0.57) = 43%
Let us remember that isotopy refers to a phenomenon in which atoms of the same element have the same atomic number but different mass numbers. This results from differences in the number of neutrons in atoms of the same element.
We can clearly see that antimony-121 has the highest percent natural abundance.
Which of the following molecules can be used in catabolic reactions to generate the carbon backbones required for gluconeogenesis?
a. glutathione, a short peptide containing glutamate, serine and histidine
b. butyrate, a short chain fatty acid
c. fructose, a monosaccharide
d. starch, a polysaccharide
Answer:
The correct option is A
Explanation:
Some amino acids, called glucogenic amino acids, when catabolized convert there carbon backbones to tricarboxylic acid (TCA) cycle intermediates. These intermediates can be subsequently metabolized into carbon dioxide and water with the release of ATP or the formation of glucose (known as gluconeogenesis.
All amino acids (with the exception of leucine and lysine) are glucogenic and can thus generate the carbon backbones required for gluconeogenesis. Thus, the correct option is a.
Determine the molarity of the sodium ions when 78.0 g Na2S is dissolved in water for a final volume of 1.0 L.
Answer:
[Na⁺] = 1.99 M
Explanation:
Na₂S is a ionic salt that can be dissociated.
Dissociation equation is:
Na₂S → 2Na⁺ + S⁻²
1 mol of sodium sulfide can give 2 moles of sodium cation.
We convert moles of salt: 78 g . 1mol / 78.06 g = 0.999 moles
As ratio is 1:2, after dissociation we have (0.999 . 2) = 1.998 moles of Na⁺
Molarity is a type of concentration.
It indicates moles of solute in 1 L of solution and in this case, we have 1 L as final voulme.
Moles of Na⁺ are 1.998 moles. Then molarity (mol/L) is:
M =1.99 mol/L
Where do reactions in a solid
generally take place?
A. All throughout the solid
B. At the center of the solid.
C. Only on opposite sides of the solid
due to repelling forces.
D. On the surface of the solid.
Answer:
A
Explanation:
because solid stick together like magnetic and can feel every vibration
Answer:D
Explanation: on the surface of a solid
A compound was analyzed and found to contain 76.57% carbon, 6.43% hydrogen, and 17.00% oxygen by mass. Calculate the empirical formula of the compound. If the molar mass of the compound is 94.11 g/mol, what is the molecular formula of the compound?
A second compound is composed of 53.30% Carbon 11.19% Hydrogen and 35.51% Oxygen by mass.Please Calculate the empirical formula of the compound of the molar mass of the compound is 90.12g/mol, what is the molecular formula for that compound?
Answer:
See explanation
Explanation:
First we divide the percentage by mass of each element by it's relative atomic mass then we divide the quotients obtained by the lowest ratio obtained in the first step.
C- 76.57/12, H= 6.43/1, O = 17.00/16
C- 6.38/1.06, H= 6.43/1.06, O= 1.06/1.06
C- 6, H- 6, O- 1
Empirical formula: C6H6O
[(12 ×6) + (6 × 1) + (16 × 1)]n=94.11
[72 + 6 +16]n = 94.11
n = 94.11/94
n= 1
Molecular formula = C6H6O
2)
C- 53.30/12, H- 11.19/1, O- 35.51/16
C- 4.44/2.22, H- 11.19/2.22, O- 2.22/2.22
C- 2, H- 5, O- 1
Empirical formula: C2H5O
[(2×12) + (5× 1) + (1×16)]n = 90.12
[24 + 5 + 16] n = 90.12
n= 90.12/45
n= 2
Molecular formula = C4H10O2
A 0.50 mol sample of COBr2 is transferred to a 9.50-L flask and heated until equilibrium is attained. Calculate the equilibrium concentrations of each species.
Answer:
Equlibrium concentration for each species ae as follows:
[CO] = 0.043 mol/L
[Br₂] = 0.043 mol/L
[COBr₂] = 0.01 mol/L
Explanation:
Let take a look at the chemical equation taking place at equilibrium
COBr2(g) ⇄ CO(g) + Br2(g)
The concentration of COBr2 i.e.
[COBr2] = no of moles/volume
= 0.50 mol/9.50 L
[COBr2] = 0.0530 mol/L
At standard conditions
Kc for COBr2 = 0.190
Now, the ICE table for the above reaction can be computed as follows:
COBr2(g) ⇄ CO(g) + Br2(g)
Initial 0.053 0 0
Change -x +x +x
Equilibrium (0.053 - x) x x
[tex]\mathsf{K_c = \dfrac{[CO][Br_2]}{[COBr_2]}}[/tex]
[tex]K_c = \dfrac{(x) (x)}{(0,053 -x)}[/tex]
[tex]0.190= \dfrac{x^2}{(0.053 -x)}[/tex]
x² = 0.190(0.053 - x)
x² = 0.01007 - 0.190x
x² + 0.190x - 0.01007 = 0
Using quadratic formula:
x ≅ 0.043 mol/L
SInce: x = [CO][Br₂] = 0.043 mol/L
[COBr₂] = 0.053 - x
[COBr₂] = 0.053 - 0.043 mol/L
[COBr₂] = 0.01 mol/L
