Chapter 6, Problem 2STP

Interpretation Introduction

Interpretation: The number of atoms of neon in a sample of neon of mass 1452.96 amu needs to be determined.

Concept introduction: The atomic mass unit is the unit of mass which is used to show the atomic weights of the atoms. It is equal to the 1/12^th of the mass of C-12 atom.

Answer to Problem 2STP

Correct Answer: Option B. 72

Explanation of Solution

The mass of neon sample is given 1452.96 amu. The atomic mass of neon from the periodic table is 20.1797 amu.

The number of atoms of neon in given mass can be calculated as follows:

  $n=\frac{1452.96\text{ amu}}{20.1797\text{ amu}}=72$

Thus, the number of atoms in given mass of Ne sample is 72.

Conclusion

Thus, the correct option is B that is 72.