According to the reaction Cl2O7 + H2O → 2HClO4, how many grams of Cl2O7 must react with an excess of H2O to form 56.2 g HClO4?

51.17g of Cl2O7

Explanation:

The equation for the reaction is given below:

Cl2O7 + H2O → 2HClO4

First, let us calculate the masses of Cl2O7 and HClO4 from the balanced equation. This is illustrated below:

Molar Mass of Cl2O7 = (2x35.5) + (16x7) = 71 + 112 = 183g/mol

Molar Mass of HClO4 = 1 + 35.5 + (16x4) = 1 + 35.5 + 64 = 100.5g/mol

Mass of HClO4 from the balanced equation = 2 x 100.5 = 201g

Now, we can obtain the mass of Cl2O7 that must react to form 56.2g HClO4. This is illustrated below:

From the equation above,

183g of Cl2O7 reacted to produced 201g of HClO4.

Therefore, Xg of Cl2O7 will react to produce 56.2g of HClO4 i.e

Xg of Cl2O7 = (183 x 56.2)/201

Xg of Cl2O7 = 51.17g

From the calculations made above, 51.17g of Cl2O7 is required to produce 56.2g of HClO4