Given the balanced equation representing a reaction:2LiOH + energy → Li2O + H2O. What is the mass of Li2O produced when 4.8 grams of LiOH reacts completely to produce 1.8 grams of H2O?

Regents Chemistry June 2026

34 Given the balanced equation representing a reaction:

2LiOH + energy → Li2O + H2O

What is the mass of Li2O produced when 4.8 grams of LiOH reacts completely to produce 1.8 grams of H2O?

(1) 4.2 g

(2) 6.6 g

(3) 3.0 g

(4) 7.8 g

Solution:

According to the law of conservation of mass, the mass of reactants (left of the arrow) is equal to the mass of the products(right of the arrow).

4.8=1.8+x

x=4.8-1.8=3.0g, choice 3 is the correct answer.

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