Question

1. what is the molecular formula of nh₂ that has a molecular weight of 32 g/mol?

Explanation:

Step1: Calculate the empirical formula weight

The empirical formula is \(NH_2\). The atomic weight of \(N\) is \(14\space g/mol\) and of \(H\) is \(1\space g/mol\).
The empirical formula weight \(M_{empirical}=(14 + 2\times1)\space g/mol=16\space g/mol\)

Step2: Find the ratio \(n\)

Let the molecular formula be \((NH_2)_n\). We know that the molecular weight \(M_{molecular}=32\space g/mol\)
We use the formula \(n=\frac{M_{molecular}}{M_{empirical}}\)
\(n = \frac{32\space g/mol}{16\space g/mol}=2\)

Step3: Determine the molecular formula

Since \(n = 2\) and the empirical formula is \(NH_2\), the molecular formula is \((NH_2)\times2=N_2H_4\)

Answer:

\(N_2H_4\)