Unit 5 Review:
1.) Balance the reaction below:
C12H22O11 + O2  CO2 + H2O
a. If you combine 12.0g of sucrose (C12H22O11) with 12.0g of oxygen, how many grams of
water could you produce?
6.19g H2O
b. What is your limiting reagent?
O2
c. What is your excess reagent?
Sucrose
d. How many grams of excess reagent will you have leftover?
1.30g excess sucrose
2.) How many grams are in 7.4 x 1024 molecules of AgNO3?
2100g AgNO3
3.) How many moles are in 9.4 x 1025 molecules of hydrogen gas?
160 moles H2
4.) What is the mass of 7.3 moles of Ca(NO3)2?
1200g Ca(NO3)2
5.) What is the empirical formula for a compound containing 26.57% potassium, 35.36% chromium,
and 38.07% oxygen?
K2Cr2O7
6.) Determine the empirical formula of the compound containing 38.7% C, 16.1% H, and 45.2% N
CH5N
7.) To find the experimental empirical formula of a compound, a student heats a piece of sulfur in a
crucible.
Data from the experiment:



Mass of empty crucible and cover - 20.740g
Mass of crucible, cover, and sulfur – 20.955g
Mass of crucible, cover, and final product - 21.170g
What is the empirical formula for the non-metal oxide that was the final product?
SO2
8.) The combustion of 2.66 grams of a compound which contains only C,H and Br yields 1.74 grams
of CO2 and 0.72 grams of H2O. What is the empirical formula of the compound?
C3H6Br2
9.) The combustion of 11.19 grams of a compound which contains only C,H and F yields 24.62
grams of CO2 and 8.4 grams of H2O. What is the empirical formula of the compound? If the
molar mass of the compound is 300.4g/mol, what is the molecular formula?
Empirical formula: C3H5F Molecular Formula: C15H25F5