Round 16: A hydrate of zinc nitrate has the formula Zn(NO3)2*xH2O. If the mass of 1 mol of anhydrous zinc nitrate is 63.37% of the mass of 1 mol of hydrate, what is the value of x?

Round 14: Olive oil is used widely in cooking. Oleic acid, a component of olive oil, contains 76.54% carbon, 12.13% hydrogen and 11.33% oxygen by mass. What is the empirical formula of oleic acid?

Round 4: A sample of pure acetic acid CH3COOH contains 1.40 x 10^23 carbon atoms. How many moles of acetic acid are in the sample?

Dinitrogen pentoxide is a white solid. When heated it decomposes to produce nitrogen dioxide and oxygen. 2N2O5(s) --> 4NO2(g) + O2(g) How many grams of oxygen gas will be produced in this reaction when 2.34g of NO2 are made?

4C3H6(g) + 6NO(g) --> 4C3H3N(g) + 6H2O(g) + N2(g) What is the limiting reagent when 126 g of C3H6 reacts with 175g of NO?

2NaN3(s) --> 3N2(g) + 2Na(s) To inflate the air bag on the driver’s side of the car, 80.0g of N2 is required. What mass of NaN3 is needed to produce 80.0g of N2?

Round 1: Naturally occurring silver exists as two isotopes. From the table above, calculate the average atomic mass of silver.

Round 10: Calculate the mass percent of nitrogen in Sr(NO3)2.

Round 15: Tartaric acid, also known as Cream of Tartar, is used in baking. Its empirical formula is C2H3O3. If 1.00mol of tartaric acid contains 3.61x1024 oxygen atoms, what is the molecular formula of tartaric acid?

Round 6: Which sample has the largest mass? A) 5.00 mol of C B) 1.50 mol of Cl2 C) 0.50 mol of C6H12O6

Round 5: Find the molar mass of K2Cr2O7 and Fe2(SO4)3.

Round 8: Vitamin B12 (C17H20N4O6) is called riboflavin. What is the mass, in grams, of a single molecule of riboflavin?