# A copper plate with a mass of 50 g was immersed in a solution of mercury chloride (2).

**A copper plate with a mass of 50 g was immersed in a solution of mercury chloride (2). The weight of the plate after the reaction was 52.74 g. How much copper was dissolved?**

The mass of the copper plate is 50 g.

The weight of the plate after the reaction is 52.74 g.

Find how much copper has dissolved.

We compose the reaction equation for this problem.

Solution:

———– Xg ————- 52.74 – 50-X

HgCl2 + Cu == CuCl2 + Hg

———- 64 —————– 201

We write down the resulting proportion.

Xr / 64 = (52.74 – 50 – x) / 201;

Next, we find x, for this we multiply the cross by the cross. We write it down.

201 x x = 64 x (52.74 – 50 – x);

201x = 64 × (2.74 – x);

We open the brackets.

201x = 175.36 – 64x;

201x + 64x = 175.36;

265x = 175.36;

x = 175.36 ÷ 265;

x = 0.66 g.

Answer: 0.66 grams of copper has dissolved.