Question

if 2 moles of h₂ react with 1 mole of o₂, how many grams of h₂o are formed? a. 18 grams b. 72 grams c. 36 grams d. 54 grams

Explanation:

Step1: Write the balanced chemical equation

The reaction between \(H_2\) and \(O_2\) to form \(H_2O\) is \(2H_2 + O_2=2H_2O\).

Step2: Calculate the moles of \(H_2O\) formed

From the balanced equation, when \(2\) moles of \(H_2\) react with \(1\) mole of \(O_2\), \(2\) moles of \(H_2O\) are formed.

Step3: Calculate the mass of \(H_2O\)

The molar mass of \(H_2O\) is \(M=(2\times1 + 16)\space g/mol= 18\space g/mol\).
Using the formula \(m = n\times M\), where \(n = 2\space mol\) (moles of \(H_2O\) formed) and \(M = 18\space g/mol\).
\(m=2\space mol\times18\space g/mol = 36\space g\)

Answer:

C. 36 grams