Question

1. a compound has the empirical formula of ch₂o. what is the molecular formula when the molecular weight is 180.0 grams? enter the correct answer in the box.

Explanation:

Step1: Calculate the empirical formula weight

The empirical formula is \(CH_2O\).
The atomic weights: \(C = 12.01\space g/mol\), \(H= 1.008\space g/mol\), \(O = 16.00\space g/mol\).
The empirical formula weight \(M_{empirical}=(12.01)+(2\times1.008)+(16.00)\)
\(M_{empirical}=12.01 + 2.016+16.00=30.026\space g/mol\)

Step2: Find the multiple \(n\)

We know that the molecular weight \(M_{molecular}=180.0\space g/mol\)
The formula \(n=\frac{M_{molecular}}{M_{empirical}}\)
\(n=\frac{180.0}{30.026}\approx6\)

Step3: Determine the molecular formula

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

Answer:

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