Question

If 156 grams of chromium react with an excess of oxygen, as shown in the balanced chemical equation below, how many grams of chromium oxide can be formed? (1 point) 4Cr + 3O2 yields 2Cr2O3

Answer 1

Answer:

=759.95 grams.

Explanation:

The molar mass of chromium is 51.9961 g/mol

Therefore the number of moles of chromium in 156 grams is:

Number of moles =mass/RAM

=156g/51.9961g/mol

=3 moles.

From the equation provided, 3 moles of chromium metal produce 2 moles of Chromium oxide.

Therefore 3 moles of chromium produce:

(3×2)/4 moles =1.5 moles of chromium oxide.

I mole of chromium oxide has a mass of 151.99 g

Thus 1.5 moles= 1.5mole ×151.99 g/mol

=759.95 grams.