Question

the mass of 75,000 molecules of oxygen is grams. (use scientific notation. use the multiplication symbol in the math palette as needed. ) mass of one molecule of oxygen = 5.3×10^(-23) gram

Explanation:

Step1: Identify the given values

We know the number of oxygen molecules $n = 75000$ and the mass of one oxygen molecule $m_1=5.3\times 10^{-23}$ grams.

Step2: Calculate the total mass

The total mass $M$ of the oxygen molecules is found by multiplying the number of molecules by the mass of one - molecule. So $M=n\times m_1$. Substitute $n = 75000=7.5\times 10^{4}$ and $m_1 = 5.3\times 10^{-23}$ grams into the formula:
\[

$$\begin{align*} M&=(7.5\times 10^{4})\times(5.3\times 10^{-23})\\ &=(7.5\times5.3)\times(10^{4}\times 10^{-23})\\ & = 39.75\times10^{4+( - 23)}\\ &=39.75\times10^{-19}\\ &=3.975\times 10^{-18}\text{ grams} \end{align*}$$

\]

Answer:

$3.975\times 10^{-18}$ grams