A chemist uses hot hydrogen gas to convert chromium(III) oxide to pure chromium. How many grams of hydrogen are needed to

convert 76 grams of chromium(III) oxide, Cr203?

3.024 g grams of hydrogen are needed to  convert 76 grams of chromium(III) oxide,

Explanation:

The reaction equation for given reaction is as follows.

Here, 1 mole of reacts with 3 moles of .

As mass of chromium (III) oxide is given as 76 g and molar mass of chromium (III) oxide is 152 g/mol.

Number of moles is the mass of substance divided by its molar mass. So, moles of is calculated as follows.

Now, moles of .given by 0.5 mol of is calculated as follows.

As molar mass of is 2.016 g/mol. Therefore, mass of is calculated as follows.

Thus, we can conclude that 3.024 g grams of hydrogen are needed to  convert 76 grams of chromium(III) oxide, .