Question

1 amu is equal to $1.66\times {10}^{-24}g$

• A. True
• B. False

Answer 1

The correct option is A True

1. Atomic mass unit (amu) is the 1/12th mass of a carbon-12 atom.
2. Atomic mass of the carbon atom is 12.
3. According to Avogadro's law, 1 mole of the substance will have $6.022\times {10}^{23}$atoms.
4. 12g of carbon contains $6.022\times {10}^{23}$atoms.
5. $$\begin{gathered} So,themassofonecarbon-12atom=\frac{12g}{6.022\times {10}^{23}} \\ 1amu=\frac{1}{12}thofmassofonecarbonatom \\ =\frac{1}{12}\times \frac{12g}{6.022\times {10}^{23}} \\ =\frac{1}{6.022\times {10}^{23}} \\ =1.66\times {10}^{-24}g \end{gathered}$$

Hence, the given statement is true.