Anshan painting recruitment

(4 points) (1) Get wet in the rain (or in humid air, or contact with acid, alkali or salt solution, etc. )? (2) The lock core is usually made of copper;

The lock body is generally painted; Lock hooks are generally stainless steel or chrome-plated nickel (only answer two kinds, each with 0.5 points).

(3)Fe 2 O 3 +6HCl=2FeCl 3 +3H 2 O

(4) Inject pencil lead powder (or graphite powder, vegetable oil, gasoline and other reasonable answers).

(1) Iron rusts easily in humid air.

(2) Copper is not easy to rust, and coating a layer of paint on the surface of iron can prevent it from rusting. The lock body is usually painted.

(3) Dilute hydrochloric acid can be used to remove rust, and the chemical equation of the reaction is: Fe 2 O 3 +6HCl=2FeCl 3 +3H 2 O.

(4) The lock core cannot rotate flexibly due to rust. You can add pencil powder to lubricate it and rotate it flexibly. You can add pencil powder.