Question

1. Calculate the molar mass of H₂CO₃.

Select one:

a. 74.04 g/mol

b. 61.02 g/mol

c. 60.01 g/mol

d. 62.03 g/mol

e. 29.02 g/mol

2. How many moles of N₂O₄ are in 76.3 g N₂O₄? The molar mass of N₂O₄ is 92.02 g/mol.

Select one:

a. 1.42 x 10-4 moles

b. 1.21 moles

c. 7.02 x 103 moles

d. 0.829 moles

e. 1.00 mole

3.Calculate the mass percent composition of lithium in Li₃PO₄.

Select one:

a. 26.75 %

b. 20.82 %

c. 55.27 %

d. 17.98 %

e. 30.72 %

4. Determine the molecular formula of a compound that is 49.48% carbon, 5.19% hydrogen, 28.85% nitrogen, and 16.48% oxygen. The molecular weight is 194.19 g/mol.

Select one:

a. C₈H₁₀N₄O₂

b. C₈H₁₂N₄O₂

c. C₄H₅N₂O

d. C₈H₁₀N₂O

5. Determine the molecular formula of a compound that has a molar mass of 183.2 g/mol and empirical formula of C₂H₅O₂.

Select one:

a. C₄H₁₀O₄

b. C₆H₁₅O₆

c. C₃H₇O₃

d. C₂H₅O₂

e. C₈H₂₀O₈