Question

1. mass of an oxygen molecule: 0.00000000000000000000000053 g

Explanation:

Step1: Recall scientific - notation rule

Scientific notation is of the form $a\times10^{n}$, where $1\leqslant|a|\lt10$ and $n$ is an integer.

Step2: Determine $a$ and $n$

For the number $0.00000000000000000000000053$, move the decimal point to the right until we get a number between 1 and 10. We move the decimal point 23 places to the right, so $a = 5.3$ and $n=-23$. The number in scientific - notation is $5.3\times 10^{-23}$ g.

Answer:

$5.3\times 10^{-23}$ g