Answer
The mass of 20,000 oxygen molecule in scientific notation is \[1.06\times {{10}^{-18}}\]gram.
Work Step by Step
It is provided that the mass of one oxygen molecule \[5.3\times {{10}^{-23}}\text{ gram}\]and it is already in scientific notation.
To find out the mass of 20,000 Oxygen molecule, so
\[20,000=2.0\times {{10}^{4}}\]
Now,mass of 20,000 oxygen molecule is:
\[\begin{align}
& 2.0\times {{10}^{4}}\times 5.3\times {{10}^{-23}}=\left( 2.0\times 5.3 \right)\times \left( {{10}^{4-23}} \right) \\
& =10.6\times {{10}^{-19}} \\
& =1.06\times {{10}^{-18}}
\end{align}\]
Hence, the mass of 20,000 oxygen molecule in scientific notation is \[1.06\times {{10}^{-18}}\]gram.
