1 One mole of an element contains which of the following?

A 6.02 atoms

B 6.02 x 1023 atoms

C 6.02 x 1023 grams

D 12 atoms

Question 2
What does Avogadro's number represent?

A the number of representative particles in a mole of a substance

B the number of atoms in a mole of a compound

C 6.02 x 1023 representative particles

both a and c
3 points
Question 3
How many atoms are in 0.654 moles of lithium chloride?

3.93 x 1023 atoms

7.87 x 1023 atoms

9.20 x 1023 atoms

1.18 x 1024 atoms
3 points
Question 4
How many molecules are in 7.90 moles of CH4?

1.31 x 10−23 molecules

7.62 x 1022 molecules

4.76 x 1024 molecules

2.30 x 1025 molecules
3 points
Question 5
Which of the following is the molar mass of NaCl?

28.00 g/mol

58.44 g/mol

811.8 g/mol

3.500 x 1025 g/mol
3 points
Question 6
Determine the molar mass of Ca(OH)2.

29.0 g/mol

38.0 g/mol

57.1 g/mol

74.1 g/mol
3 points
Question 7
If you are given the mass of a substance sample in grams, what is the first step you should take to determine how many representative particles are in that sample?

find the molar mass of the substance

convert the grams to particles

convert the mass to moles

convert the moles to particles
3 points
Question 8
How many oxygen atoms are in 3.21 x 1022 molecules of CH3OH?

1.9 x 1023 atoms

3.21 x 1022 atoms

6.42 x 1022 atoms

1.56 x 1023 atoms
3 points
Question 9
Percent composition identifies the amount (in percent) of each element present in a compound.

TRUE

FALSE
2 points
Question 10
The percent composition of acetic acid, HC2H3O2, is:

20% carbon, 2% hydrogen, 27% oxygen

40% carbon, 7% hydrogen, 53% oxygen

23% carbon, 7% hydrogen, 70% oxygen

Cannot be determined from the information given