Chemistryhard · Past Paper

How many grams of Oxygen are needed to burn 12g of Magnesium completely? (Mg=24, O=16)

A8g
B16g
C32g
D4g

✓ Correct Answer: A8g

2Mg + O2 -> 2MgO. 48g Mg reacts with 32g O2. So 12g Mg reacts with (32/48)*12 = 8g O2.

Share this question

More from Chemistry