Question

bellringer
adimensional analysis to complete the following. round to 3 sig figs
convert 17.4 moles of c₃h₈ into grams.
convert 14.5 grams of platinum (pt) into atoms

Explanation:

Step1: Calculate molar mass of \(C_3H_8\)

The molar mass of \(C\) is \(12.01\space g/mol\) and of \(H\) is \(1.008\space g/mol\).
For \(C_3H_8\), \(M=(3\times12.01 + 8\times1.008)\space g/mol=(36.03+8.064)\space g/mol = 44.094\space g/mol\)

Step2: Use dimensional analysis

We know that \(mass = moles\times molar\space mass\)
Given \(n = 17.4\space mol\)
\(m=17.4\space mol\times44.094\space g/mol\)
\(m = 17.4\times44.094\space g\)
\(m=767.2356\space g\)

Step3: Round to 3 significant figures

Rounding \(767.2356\) to 3 significant figures gives \(767\space g\)

Answer:

\(767\space g\)