CHEMISTRY I Philippines INHS
Homework: Stoichiometry
Part IA: Problem Solving
Directions: Solve the following questions. Present your solutions in a neat and organized manner. Unclear solutions
may be subjected to point deductions. Box your final answer. Your work will be graded based on the grading rubric
provided at the end of the paper. Each item is worth 10 points.
1. What is the empirical formula of a compound found to contain 13.5g Ca, 10.8g O, and 0.675g H?
2. Calculate the empirical formula of Nutrasweet, which is found to have 57.14% C, 6.16% H, 9.52% N, and
27.18% O.
3. A large family of boron-hydrogen compounds has the general formula BxHy. One member of this family
contains 88.5% B; the remainder is hydrogen. What is its empirical formula?
4. Mandelic acid is an organic acid composed of carbon (63.15%), hydrogen (5.30%), and oxygen (31.55%). Its
molar mass is 152.14 g/mol. Determine the empirical formula of the acid.
5. An unknown compound contains 16.22% carbon, 2.72% hydrogen, 37.84% nitrogen, and 43.22% oxygen by
mass. Determine the empirical formula of the compound.
ANSWERS:
1
, 2
Homework: Stoichiometry
Part IA: Problem Solving
Directions: Solve the following questions. Present your solutions in a neat and organized manner. Unclear solutions
may be subjected to point deductions. Box your final answer. Your work will be graded based on the grading rubric
provided at the end of the paper. Each item is worth 10 points.
1. What is the empirical formula of a compound found to contain 13.5g Ca, 10.8g O, and 0.675g H?
2. Calculate the empirical formula of Nutrasweet, which is found to have 57.14% C, 6.16% H, 9.52% N, and
27.18% O.
3. A large family of boron-hydrogen compounds has the general formula BxHy. One member of this family
contains 88.5% B; the remainder is hydrogen. What is its empirical formula?
4. Mandelic acid is an organic acid composed of carbon (63.15%), hydrogen (5.30%), and oxygen (31.55%). Its
molar mass is 152.14 g/mol. Determine the empirical formula of the acid.
5. An unknown compound contains 16.22% carbon, 2.72% hydrogen, 37.84% nitrogen, and 43.22% oxygen by
mass. Determine the empirical formula of the compound.
ANSWERS:
1
, 2
