Empirical Formulas Practice
Show all of the problem-solving steps to determine the empirical formula of each compound shown below, according to the problem setup provided in the lesson. Handwrite the work for each problem. Upload as a single file.
1) Determine the empirical formula of ethyl acetate, which has a percent composition of: 48.64 % C, 8.16 % H, 43.20 % O.
2) Determine the empirical formula of a sample of the mineral ilmenite, which contains, 5.41 g Fe, 4.64 g Ti, and 4.65 g O.
3) Determine the empirical formula for a compound which contains 32.8% chromium and 67.2% chlorine.
4) What is the empirical formula for a compound which contains 67.1% zinc and the remainder is oxygen?
5) A 175.0 g sample contains 56.15 g C, 9.43 g H, 74.81 g O, 13.11 g N, and 21.49 g Na. Determine the compound’s empirical formula.
Molecular Formulas Practice
1. Define empirical formula.
2. Define molecular formula.
3. The empirical formula of a compound of phosphorus and oxygen was found to be P2O5. Experimentation shows that the molar mass of this compound is 283.89g/mol. What is the compound’s molecular formula?
4. A sample with a molar mass of 34.00 g/mol is found to consist of 0.44g H and 6.92g O. Find its molecular formula. (Hint: Find the empirical formula first).
5. A compound with a molar mass of 42.08 g/mol is composed of 85.4% carbon and 14.36% hydrogen. Find its molecular formula.(Hint: Find the empirical formula first).
Percent Composition Practice Problems
Print out or hand write each the the problems below, leaving adequate space between each problem. Show all problem-solving steps for each problem below, as demonstrated in the lesson. Create a single file by copying and pasting a picture of the problem-solving steps under each problem. Upload the document.
1) Determine the percentage composition of ethanol (C2H5OH).
2) Determine the % by mass of each element in calcium chloride.
3) Calculate the percent composition of sodium sulfate.
4) Which has the larger percent by mass of sulfur, H2SO3 or H2S2O8?
5) What is the percent composition of phosphoric acid (H3PO4)?