Question 1

How many oxygen atoms are there in 0.25 mole of CO2?

Accepted Answer

A)  0.50
B)  0.25
C)  3.0 x 1023 
D)  1.5 x 1023 
E)  4.2 x 10-25 F) C) and E)
G) B) and E)

Question 2

Calculate the molarity of a solution consisting of 73.8 g NaCl in 1.50 L of solution?

Accepted Answer

A)  0.528 M
B)  1.19 M
C)  49.2 M
D)  1.26 M
E)  0.842 MF) C) and D)
G) A) and B)

Question 3

The molecular formula of the molecules in the figure is: 4  B) N2H4  C) NH3  D) N2H3  E) N4H2 " class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)  NH4 
B)  N2H4 
C)  NH3 
D)  N2H3 
E)  N4H2 F) A) and B)
G) A) and C)

Question 4

Methyl butyrate is a compound that is partially responsible for the flavor of apples.It consists of 58.80% C, 9.87% H, and 31.33% O.What is the empirical formula of methyl butyrate?

Accepted Answer

A)  C6H10O3 
B)  C5H10O2 
C)  CH2O
D)  C4.9H9.8O1.9 
E)  C4H9O2 F) A) and C)
G) D) and E)

Question 5

If 100.0 mL of 0.426 M NaOH solution is diluted to 500.0 mL, what is the concentration of the diluted solution?

Accepted Answer

A)  0.0426 M
B)  0.0852 M
C)  0.117 M
D)  2.13 M
E)  8.52 x 103 MF) A) and C)
G) C) and D)

Question 6

How many formula units are in 2.0 moles of Fe(NO3) 2?

Accepted Answer

A)  1.2 x 1024 
B)  3.6 x 1024 
C)  1.1 x 1025 
D)  2.0
E)  18F) A) and D)
G) B) and D)

Question 7

Calculate the molarity of a solution consisting of 60.0 g of NaOH in 1.50 L of solution.

Accepted Answer

A)  40.0 M
B)  1.00 M
C)  1.74 M
D)  1.50 M
E)  1.60 x 103 MF) A) and D)
G) A) and C)

Question 8

How many formula units are in 0.25 mole of Na2O?

Accepted Answer

A)  4.5 x 1023 
B)  0.75
C)  1.5 x 1023 
D)  4.2 x 10-25 
E)  0.25F) B) and D)
G) A) and E)

Question 9

How many oxygen atoms are present in 1.50 mol of Zn(NO3) 2?

Accepted Answer

A)  4.50 atoms
B)  9.00 atoms
C)  9.03 x 1023 atoms
D)  5.42 x 1024 atoms
E)  1.49 x 10-23 atomsF) None of the above
G) A) and C)

Question 10

How many nitrogen atoms are present in 0.150 mol of Zn(NO3) 2?

Accepted Answer

A)  9.03 x 1022 atoms
B)  1.81 x 1023 atoms
C)  4.98 x 10-25 atoms
D)  0.300 atoms
E)  0.450 atomsF) C) and D)
G) A) and B)

Question 11

Which of the following statements regarding empirical formulas, molecular formulas, and percent composition is correct?

Accepted Answer

A)  The empirical formula and molecular formula of a given compound are always the same.
B)  Two compounds having different percent compositions of the same two elements are not the same compound.
C)  The empirical formula and molecular formula of a given compound are never the same.
D)  Data on the percent composition of the elements in a given compound is insufficient to determine the empirical formula of the compound.
E)  The compound S2Cl2 would have the same empirical and molecular formulas.F) A) and D)
G) A) and E)

Question 12

If 7.50 x 1024 molecules of a substance have a mass of 454 g, what is the molar mass of the substance?

Accepted Answer

A)  2.73 x 1026 g/mol
B)  3.41 x 1027 g/mol
C)  5.65 x 103 g/mol
D)  36.5 g/mol
E)  12.5 g/molF) B) and D)
G) B) and C)

Question 13

Which of the following sets of formulas is correct for the molecules in the figure? 2SO3, SCl5, C2H5  B) H2SO4, SCl5, C2H5  C) H2SO4, SCl6, C2H6  D) H2SO4, SCl6, CH6  E) H2SO3, SCl6, C2H6 " class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)  H2SO3, SCl5, C2H5 
B)  H2SO4, SCl5, C2H5 
C)  H2SO4, SCl6, C2H6 
D)  H2SO4, SCl6, CH6 
E)  H2SO3, SCl6, C2H6 F) B) and C)
G) C) and E)

Question 14

Which of the following statements regarding empirical formulas, molecular formulas, and percent composition is correct?

Accepted Answer

A)  The compounds NO2 and N2O4 have the same empirical formula.
B)  The compounds NO2 and N2O4 have the same molecular formula.
C)  The empirical formula of H2O2 is H2O.
D)  The empirical formula of N2O5 is NO2.5.
E)  The compounds PCl3 and PCl5 would have the same percent composition.F) C) and D)
G) A) and D)

Question 15

How many molecules of HCl are present in 0.250 mol of HCl?

Accepted Answer

A)  4.15 x 10-25 molecules
B)  1.51 x 1023 molecules
C)  2.41 x 1024 molecules
D)  9.11 molecules
E)  0.250 moleculesF) A) and E)
G) A) and B)

Question 16

The process of diluting a solution in the laboratory is much like preparing juice from a canned concentrate of the juice.

Accepted Answer

A) True 
 B)False

Question 17

Rank the following elements in order from least to most number of moles of atoms in a 10.0 g sample: Sn, Si, Se, S

Accepted Answer

A)  Sn 
B)  Si 
C)  Si 
D)  S 
E)  Se < Sn < S < SiF) None of the above
G) A) and C)

Question 18

The substance in the figure with the most atoms per mole is NaCl.

Accepted Answer

A) True 
 B)False

Question 19

Which of the following statements is incorrect?

Accepted Answer

A)  PH3 has 3 times as many hydrogen atoms as phosphorus atoms.
B)  MgO has an equal number of magnesium ions and oxygen ions.
C)  BaBr2 has half as many barium ions as bromide ions.
D)  N2O5 has 2.5 times as many nitrogen atoms as oxygen atoms.
E)  SF4 has 4 times as many fluorine atoms as sulfur atoms.F) A) and E)
G) B) and E)

Question 20

Which of the following statements is incorrect?

Accepted Answer

A)  H2SO3 has 1.5 times as many oxygen atoms as hydrogen atoms.
B)  Fe2(SO4) 3 has six times as many oxygen atoms as iron ions.
C)  N2H4 has twice as many hydrogen atoms as nitrogen atoms.
D)  MgF2 has half as many fluoride ions as magnesium ions.
E)  Carbon dioxide has twice as many oxygen atoms as carbon atoms.F) A) and D)
G) All of the above

Exam 4: Chemical Composition

How many oxygen atoms are there in 0.25 mole of CO2?

Correct AnswerverifiedShow Answer

Which of the following statements is incorrect?

Correct AnswerverifiedShow Answer

Calculate the molarity of a solution consisting of 73.8 g NaCl in 1.50 L of solution?

Correct AnswerverifiedShow Answer

How many nitrogen atoms are present in 0.150 mol of Zn(NO3) 2?

Correct AnswerverifiedShow Answer

The molecular formula of the molecules in the figure is:

Correct AnswerverifiedShow Answer

The substance in the figure with the most atoms per mole is NaCl.

Correct AnswerverifiedShow Answer

Which of the following statements regarding empirical formulas, molecular formulas, and percent composition is correct?

Correct AnswerverifiedShow Answer

Calculate the molarity of a solution consisting of 60.0 g of NaOH in 1.50 L of solution.

Correct AnswerverifiedShow Answer

How many formula units are in 0.25 mole of Na2O?

Correct AnswerverifiedShow Answer

If 100.0 mL of 0.426 M NaOH solution is diluted to 500.0 mL, what is the concentration of the diluted solution?

Correct AnswerverifiedShow Answer

How many oxygen atoms are present in 1.50 mol of Zn(NO3) 2?

Correct AnswerverifiedShow Answer

Rank the following elements in order from least to most number of moles of atoms in a 10.0 g sample: Sn, Si, Se, S

Correct AnswerverifiedShow Answer

How many molecules of HCl are present in 0.250 mol of HCl?

Correct AnswerverifiedShow Answer

Which of the following sets of formulas is correct for the molecules in the figure?

Correct AnswerverifiedShow Answer

The process of diluting a solution in the laboratory is much like preparing juice from a canned concentrate of the juice.

Correct AnswerverifiedShow Answer

How many formula units are in 2.0 moles of Fe(NO3) 2?

Correct AnswerverifiedShow Answer

Which of the following statements is incorrect?

Correct AnswerverifiedShow Answer

If 7.50 x 1024 molecules of a substance have a mass of 454 g, what is the molar mass of the substance?

Correct AnswerverifiedShow Answer

Which of the following statements regarding empirical formulas, molecular formulas, and percent composition is correct?

Correct AnswerverifiedShow Answer

Methyl butyrate is a compound that is partially responsible for the flavor of apples.It consists of 58.80% C, 9.87% H, and 31.33% O.What is the empirical formula of methyl butyrate?

Correct AnswerverifiedShow Answer

How many oxygen atoms are there in 0.25 mole of CO₂?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

How many nitrogen atoms are present in 0.150 mol of Zn(NO₃) ₂?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

How many formula units are in 0.25 mole of Na₂O?

Correct Answer
verified

Correct Answer
verified

How many oxygen atoms are present in 1.50 mol of Zn(NO₃) ₂?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

How many formula units are in 2.0 moles of Fe(NO₃) ₂?

Correct Answer
verified

Correct Answer
verified

If 7.50 x 10²⁴ molecules of a substance have a mass of 454 g, what is the molar mass of the substance?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified