Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Number density equation is given by

$ n= \dfrac{(N_A)\rho}{M} $

where $ N_A =6.023\times10^{23} mol^{-1} $

$ \rho=8.02\ g/cm^3 $(at 1500 degree celsius.)

$M=63.546*1.6605\times10^{-24} g$

Whats wrong with this values? I am failed to calculate number density.

share|cite|improve this question

In your formula $M$ is the molar mass given in $g \,\text{mol}^{-1}$ so for your compound $M=63.546 \,g \,\text{mol}^{-1}$ and the density in atoms per cubic centimeter will be $n=7.6 \cdot 10^{22}$$\text{cm}^{-3}$.

share|cite|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.