The Grass Doctor

AP Chem??????

A. Solutions of sodium carbonateand silver nitrate react to form solid silver carbonate and a solution of sodium nitrate. A solution containing 5.00g of sodium carbonate is mixed with one containing 5.00g of silver nitrate. After the reaction is complete the solutions are evaporated to dryness, leaving a mixture of salts. how many grams of sodium carbonate, silver nitrate, silver carbonate, and sodium nitrate and present after the reaction is complete? B. Gallium (Ga) consists of two naturaly occuring isotopes with masses of 68.926 and 70. 926 amu. 1. how many protons and neutrons are in the nucleus of each isotope? Write the complete atomic symbol for each, showing the atomic number and mass number. 2. the average atomic mass of Ga is 69.72 amy. Calculate the abundance of each isotope. C. Four common nitrogen-containing fertilizers are ammonia, ammonium nitrate, ammonium sulfate, and urea [(NH2)2CO] How much of each compound must be used to provide 1.00 kg of nitrogen. Thx!

Public Comments

1. A. Na2CO3 + 2 AgNO3 >> 2 NaNO3 + Ag2CO3 MM of Na2CO3 = 106 g/mol Mole Na2CO3 =5.00 / 106 = 0.0472 MM AgNO3 = 169.87 g/mol Mole AgNO3 =5.00 / 169.87 = 0.0294 The ratio between Na2CO3 and AgNO3 is 1 : 2 so AgNO3 is the limiting reactant 1 : 2 = x : 0.0294 x = 0.0147 mole Na2CO3 needed for the reaction mole Na2CO3 in excess = 0.0472 - 0.0147 = 0.0325 ( ==> 0.0325 mol x 106 g/mol = 3.45 g We would get 0.0294 mole of NaNO3 ( ==> 0.0294 mol x 85 g/mol = 2.50 g) We wolud get 0.0294 / 2 = 0.0147 mole of Ag2CO3 ( ==> 0.0147 x 275.7 g/mol = 4.05 g) AgNO3 is not present after the reaction 69 .....Ga 32 protons and 37 neutrons 32 71 .....Ga 32 protons and 39 neutrons 32 69- Ga ==> 60.1 % 71- Ga ==> 39.9 %