Question

1. Calcium carbonate (a weak base) reacts with nitric acid (a strong acid) quantitatively in the following reaction to form calcium nitrate, water and carbon dioxide: How many kg of carbon dioxide (CO2) are formed per kg of CaCO3 reacted? Presume that there is an excess of HNO3 available.

2. Metallic sodium reacts vigorously with liquid bromine in the following reaction: 1 kg of Na is brought into contact with 3 kg of liquid bromine. Presuming that the reaction is quantitative and proceeds to completion, determine the limiting reagent and the quantity of NaBr formed. Determine the amount of excess reagent remaining after the reaction is complete.

Answer 1

1)

CaCO3 + 2HNO3 -------------------------> Ca(NO3)2 + CO2 + H2O

100 g                                                                            44 g

0.1kg                                                                             0.44 kg

1 kg                                                                                ?

0.1 kg of CaCO3 ----------------------------> 0.44 kg of CO2

1 kg of CaCO3 -------------------------------> 1 x 0.44 / 0.1 kg CO2

CO2 mass = 4.4 kg

for every Kg of CaCO3 there will be 4.4 kg of CO2 will be produced.