Question

1. a fire in the lab is calculated to consume 17.9 moles of oxygen (o₂), how many grams of o₂ is this?

Explanation:

Step1: Find the molar mass of \(O_2\)

The molar mass of \(O\) (oxygen atom) is \(16\space g/mol\). For \(O_2\), \(M = 2\times16=32\space g/mol\)

Step2: Use the formula \(m = n\times M\)

Here, \(n = 17.9\space mol\) (moles of \(O_2\)) and \(M = 32\space g/mol\) (molar mass of \(O_2\)). Then \(m=17.9\times32\)

$$m=(18 - 0.1)\times32=18\times32-0.1\times32=576 - 3.2 = 572.8\space g$$

Answer:

\(572.8\space g\)