In the reaction list below, 18 g of carbon react with oxygen to produce 72 g of carbon dioxide. What mass of oxygen would be needed in the reaction?
a 18 g
b 54 g
c 72 g
d 90 g

Mass of oxygen = 54 gram

Explanation:

Given:

In a reaction:

Mass of carbon = 18 gram

Mass of carbon dioxide = 72 gram

Find:

Mass of oxygen needed = ?

Computation:

According to law of conservation of mass:

⇒ Sum of Mass of reactants = Sum of Mass of product

So,

⇒ 18 gram + Mass of oxygen = 72 gram

⇒ Mass of oxygen = 72 gram - 18 gram

⇒ Mass of oxygen = 54 gram

the first letter must be uppercase?