Question

1. a molecule has an empirical formula of ch₂o and a molecular weight of 180 g/mol. what is the molecular formula?

Explanation:

Step1: Calculate the empirical formula weight

The empirical formula is \(CH_2O\). The atomic weights are \(C = 12\space g/mol\), \(H= 1\space g/mol\), \(O = 16\space g/mol\).
The empirical formula weight \(M_{empirical}=(1\times12)+(2\times1)+(1\times16)=30\space g/mol\)

Step2: Find the ratio \(n\)

We know that the molecular weight \(M_{molecular}=180\space g/mol\). The ratio \(n=\frac{M_{molecular}}{M_{empirical}}\)
\(n=\frac{180}{30} = 6\)

Step3: Determine the molecular formula

Multiply each sub - script in the empirical formula by \(n\).
The empirical formula \(CH_2O\), after multiplying by \(n = 6\), the molecular formula is \(C_{6}H_{12}O_{6}\)

Answer:

\(C_{6}H_{12}O_{6}\)