Question 1

Which of the following is already in its empirical formula?

Accepted Answer

A)  C22H34O10
B)  C6H6
C)  C6H12O3
D)  C5H12O2
E)  none of the aboveF) B) and E)
G) B) and C)

Question 2

The mole has a value of 6.023 × 1022.

Accepted Answer

A) True 
 B)False

Question 3

If a sample of carbon dioxide contains 3.8 moles of oxygen atoms,how many moles of carbon dioxide are in the sample?

Accepted Answer

A)  1.9
B)  3.8
C)  7.6
D)  11.4
E)  none of the aboveF) A) and E)
G) All of the above

Question 4

One mole of (NH4) 2HPO4 contains how many moles of hydrogen atoms?

Accepted Answer

A)  4
B)  2
C)  8
D)  9
E)  none of the aboveF) B) and D)
G) B) and C)

Question 5

What is the mass percent of carbon in oxalic acid,H2C2O4?

Accepted Answer

A)  2.24
B)  13.3
C)  26.7
D)  34.5
E)  none of the aboveF) A) and E)
G) A) and D)

Question 6

Determine the empirical formula of a compound containing 83% potassium and 17.0% oxygen.

Accepted Answer

A)  KO
B)  KO2
C)  K2O3
D)  K2O
E)  none of the aboveF) D) and E)
G) C) and D)

Question 7

How many moles of iron are contained in 1.75 kg of iron?

Accepted Answer

A)  3.13 × 10-2
B)  3.13 × 10-4
C)  31.3
D)  3.13 × 104
E)  none of the aboveF) C) and D)
G) A) and B)

Question 8

The empirical formula for C6H6 is C3H3.

Accepted Answer

A) True 
 B)False

Question 9

One mole of argon has more atoms in it than one mole of neon.

Accepted Answer

A) True 
 B)False

Question 10

One mole of water contains 6.022 × 1023 hydrogen atoms.

Accepted Answer

A) True 
 B)False

Question 11

The correct formula for calculating mass percent of X in compound XY is:  = Mass % X

Accepted Answer

A) True 
 B)False

Question 12

A molecule that has an empirical formula of HO and a molar mass of 34.02 gram must have a molecular formula of H2O2.

Accepted Answer

A) True 
 B)False  True

Question 13

One mole of lead(II)nitrate contains six moles of oxygen atoms.

Accepted Answer

A) True 
 B)False  True

Question 14

One mole of boron has a mass of ________ g.

Accepted Answer

A)  9.012
B)  6.022 × 1023
C)  5
D)  10.811
E)  none of the aboveF) B) and E)
G) B) and C)

Question 15

Calculate the molar mass of calcium nitrate.

Accepted Answer

A)  136.03 g/mol
B)  102.09 g/mol
C)  132.10 g/mol
D)  164.10 g/mol
E)  none of the aboveF) B) and E)
G) B) and D)

Question 16

The molar mass of a compound in grams per mole is numerically equal to the formula mass of the compound in atomic mass units.

Accepted Answer

A) True 
 B)False

Question 17

In comparing 1 mole of carbon atoms to one mole of magnesium atoms,which statement is TRUE?

Accepted Answer

A)  The mass of 1 mole of carbon is greater than the mass of 1 mole of magnesium.
B)  The mass of 1 mole of magnesium is greater than the mass of 1 mole of carbon.
C)  The mass of 1 mole of carbon is the same as the mass of 1 mole of magnesium.
D)  There are more atoms in 1 mole of magnesium than in 1 mole of carbon.
E)  none of the aboveF) A) and D)
G) A) and C)

Question 18

How many moles of Pb are in 4.71 × 1021 Pb atoms?

Accepted Answer

A)  0.00782
B)  2.84 × 1045
C)  207.2
D)  6.022 × 1023
E)  none of the aboveF) B) and E)
G) A) and B)

Question 19

One mole of oxygen gas has a mass of ________ g.

Accepted Answer

A)  16.0
B)  32.0
C)  6.022 × 1023
D)  8
E)  none of the aboveF) A) and B)
G) B) and D)

Question 20

How many molecules of sulfur trioxide are in 78.0 grams?

Accepted Answer

A)  5.87 × 1023
B)  7.33 × 1023
C)  3.76 × 1027
D)  0.974
E)  none of the aboveF) A) and E)
G) All of the above A

Exam 6: Chemical Composition

Which of the following is already in its empirical formula?

Correct AnswerverifiedShow Answer

The mole has a value of 6.023 × 1022.

Correct AnswerverifiedShow Answer

If a sample of carbon dioxide contains 3.8 moles of oxygen atoms,how many moles of carbon dioxide are in the sample?

Correct AnswerverifiedShow Answer

One mole of (NH4) 2HPO4 contains how many moles of hydrogen atoms?

Correct AnswerverifiedShow Answer

What is the mass percent of carbon in oxalic acid,H2C2O4?

Correct AnswerverifiedShow Answer

Determine the empirical formula of a compound containing 83% potassium and 17.0% oxygen.

Correct AnswerverifiedShow Answer

How many moles of iron are contained in 1.75 kg of iron?

Correct AnswerverifiedShow Answer

The empirical formula for C6H6 is C3H3.

Correct AnswerverifiedShow Answer

One mole of argon has more atoms in it than one mole of neon.

Correct AnswerverifiedShow Answer

One mole of water contains 6.022 × 1023 hydrogen atoms.

Correct AnswerverifiedShow Answer

The correct formula for calculating mass percent of X in compound XY is: = Mass % X

Correct AnswerverifiedShow Answer

A molecule that has an empirical formula of HO and a molar mass of 34.02 gram must have a molecular formula of H2O2.

Correct AnswerverifiedTrue

One mole of lead(II)nitrate contains six moles of oxygen atoms.

Correct AnswerverifiedTrue

One mole of boron has a mass of ________ g.

Correct AnswerverifiedShow Answer

Calculate the molar mass of calcium nitrate.

Correct AnswerverifiedShow Answer

The molar mass of a compound in grams per mole is numerically equal to the formula mass of the compound in atomic mass units.

Correct AnswerverifiedShow Answer

In comparing 1 mole of carbon atoms to one mole of magnesium atoms,which statement is TRUE?

Correct AnswerverifiedShow Answer

How many moles of Pb are in 4.71 × 1021 Pb atoms?

Correct AnswerverifiedShow Answer

One mole of oxygen gas has a mass of ________ g.

Correct AnswerverifiedShow Answer

How many molecules of sulfur trioxide are in 78.0 grams?

Correct AnswerverifiedA

Correct Answer
verified

The mole has a value of 6.023 × 10²².

Correct Answer
verified

Correct Answer
verified

One mole of (NH₄) ₂HPO₄ contains how many moles of hydrogen atoms?

Correct Answer
verified

What is the mass percent of carbon in oxalic acid,H₂C₂O₄?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

The empirical formula for C₆H₆ is C₃H₃.

Correct Answer
verified

Correct Answer
verified

One mole of water contains 6.022 × 10²³hydrogen atoms.

Correct Answer
verified

Correct Answer
verified

A molecule that has an empirical formula of HO and a molar mass of 34.02 gram must have a molecular formula of H₂O₂.

Correct Answer
verified
True

Correct Answer
verified
True

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

How many moles of Pb are in 4.71 × 10²¹ Pb atoms?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
A