G11 Chemistry - Class 9 Review

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?

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

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

Round 12: A compound consists of 17.6% hydrogen and 82.4% nitrogen. Determine the empirical formula of the compound.

The following reaction proceeds with an 89% yield. C2H5OBr + NaOH --> C2H4O + NaBr + H2O What mass of C2H4O can be obtained when 3.61 x 10^23 molecules of C2H5OBr react with excess sodium hydroxide?

Round 3: A small pin contains 0.0178 mol of iron (Fe). How many atoms of iron are in the pin?

Round 11: Indigo (C16H10N2O2) is the common name of the dye that gives blue jeans their characteristic colour. Calculate the mass of oxygen in 25.0 g of indigo.

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

Round 13: Compound X contains 69.9% carbon, 6.86% hydrogen, and 23.3% oxygen. Determine the empirical formula of Compound X.

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?

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 9: Find the percentage composition of a pure substance that contains 7.22g nickel, 2.53g phosphorus and 5.25g oxygen.

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 2: Rubidium ignites spontaneously when exposed to oxygen to form Rb2O. Rubidium exists as two isotopes: Rb-85 (84.91u) and Rb-87 (86.91u). If the average atomic mass of Rubidium is 85.47u, determine the percentage abundance of Rb-85.

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 7: Sodium chloride (NaCl) can be used to melt snow. How many moles of sodium chloride are in a 10kg bag?

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?

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