Rust removal (ferric oxide)

Manufacture of pharmaceuticals (hydrochloric acid that helps digest human gastric juice)

Common names: caustic soda, fire soda, caustic soda

Dissolves in water and releases a lot of heat

It easily absorbs moisture in the air and deliquesces, so it needs to be sealed and stored.

Common names: slaked lime, slaked lime

Calcium oxide water = calcium hydroxide

Use indicators or pH test paper

Reacts with more reactive metals to produce hydrogen

Use indicators or pH test paper

Precipitates with metal ions such as copper ions, iron ions, aluminum ions, and magnesium ions.

Adding acid solution produces carbon dioxide that turns clear limewater cloudy

Adding silver nitrate solution produces silver chloride precipitate

Add a solution containing barium ions to produce barium sulfate precipitation

Reacts with alkaline solution to form corresponding precipitate

Heating: sodium bicarbonate produces sodium carbonate, water and carbon dioxide

Add calcium chloride solution: the white precipitate is sodium carbonate

Add a small amount of hydrochloric acid: sodium bicarbonate is what immediately generates carbon dioxide; sodium bicarbonate and hydrochloric acid first generate sodium carbonate, and then there is insufficient hydrochloric acid to generate carbon dioxide.

Prepare normal saline (0.9% NaCl)

food condiments

melt the snow on the road

Instruments: glass rod, beaker, funnel

Function of glass rod: Stirring, accelerating dissolution; drainage, preventing liquid splashing