C3H8 + 5 O2 → 3 CO2 + 4 H2O a. 3.80 moles of oxygen are used up in the reaction. How many grams of water are produced?

b. How many grams of oxygen does it take to produce 90.6 grams of Carbon Dioxide?

¹/3 C3H8(g) + ⁵/3 O2(g)

Explanation:

The coefficient before every molecule is representative of the number of moles. We can represent it in ration form so as to calculate the question;

C₃H₈(g) + 5 O₂(g) → 3 CO₂(g) + 4 H₂O(l) means;

For every 1 mole of C₃H₈(g) and 5 moles of  O₂(g) produces  3 moles of  CO₂(g) and 4 moles of H₂O(l).

Therefore to produce 1.00 mole of CO₂(g);

We represent it in ratio;

C₃H₈(g) : CO₂(g)

1  :     3

For more on evaluating moles in chemical reactions check out;

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