Calcium nitrate

Calcium nitrate, also known as Norwegian saltpeter, is a chemical compound. Its chemical formula is Ca(NO3)2. It contains calcium and nitrate ions.
Properties.
Calcium nitrate is a colorless solid. It is an oxidizing agent. It absorbs water from the air. It decomposes to make nitrogen dioxide and calcium oxide when heated. 
Preparation.
Calcium nitrate is made by reacting calcium hydroxide or calcium carbonate with nitric acid. It is made when nitric acid reacts with calcium phosphate. It can be made by reacting ammonium nitrate and calcium hydroxide.
Uses.
Calcium nitrate is used in fertilizers to add nitrogen to the soil. It can be complexed with urea to make a different nitrogen fertilizer.