### Theory:

What is physical property?
A physical property is a property of matter that can be observed and measured without changing the sample's chemical identity.
Physical Properties of Copper:

(a). Copper is a reddish-brown metal. (You can see your kitchen utensils)

Reddish-brown copper

(b). Copper has a high lustre (Shiny and bright appearance).

Shiny copper vessels

(c). Copper has a high density of $$8.9$$ (Aluminium density is $$2.7$$).

High dense copper

(d). Copper has a high melting point ($$1356$$°C). (We cant melt copper in regular heating)

Copper welding (melted copper)

What is a chemical property?
A chemical property is a property of a substance that can be seen when it undergoes a chemical reaction.
Chemical Properties of Copper:

(i) Action of air and moisture:

Copper gets coated with a green layer of basic copper carbonate in the presence of $$CO_2$$ and moisture.
$$2Cu$$ + $$O2$$ + $$CO_2$$ + $$H_2O$$ → $$CuCO_3$$.$$Cu(OH)_2$$
(Copper)                                      (Copper carbonate)

(ii) Action of heat:

On heating at various temperatures in the presence of oxygen, copper forms two types of oxides, $$CuO$$ and $$Cu_2O$$.

(copper II oxide-black)

(copper I oxide-red)

(iii) Action of acids:

(a). With dilute $$HCl$$ and dilute $$H_2SO_4$$:

In the presence of air, copper dissolves in dilute $$HCl$$ and $$H_2SO_4$$.
In the absence of air, dilute acids such as $$HCl$$ and $$H_2SO_4$$ have no action on copper.

$$2Cu$$ + $$4HCl$$ + $$O_2$$(air) → $$(2CuCl_2$$ + $$2H_2O$$

(b). With dilute $$HNO_3$$:

Copper reacts with dilute $$HNO_3$$ to produce nitric oxide gas.

$$3Cu$$ + $$8HNO_3$$ → $$3Cu(NO_3)_2$$ + $$2NO$$↑ + $$4H_2O$$

(iv) Action of chlorine:

Chlorine reacts with copper to form copper(II) chloride.

$$Cu$$ + $$Cl_2$$ → $$CuCl_2$$

(v) Action of alkalis:

Alkalis do not attack copper.