A grain of sand has a mass of approximately [tex]2.3 \times 10^{-4}[/tex] grams. If a beach contains around [tex]45 \times 10^{12}[/tex] grains of sand, what is the total mass of the sand on the beach? Express your answer in scientific notation.

To find the total mass of sand on the beach, we need to calculate the product of the mass of a single grain of sand and the total number of grains on the beach. Here’s how you can do it:

1. Understand the values given:
- Each grain of sand has a mass of approximately [tex]\(2.3 \times 10^{-4}\)[/tex] grams.
- The beach contains about [tex]\(45 \times 10^{12}\)[/tex] grains of sand.

2. Multiply the mass of one grain by the total number of grains:
[tex]\[
\text{Total mass} = (2.3 \times 10^{-4}) \times (45 \times 10^{12})
\][/tex]

3. Combine the numerical parts and the powers of ten separately:
- First, multiply the numerical parts: [tex]\(2.3 \times 45 = 103.5\)[/tex]
- Next, multiply the powers of ten: [tex]\(10^{-4} \times 10^{12} = 10^{8}\)[/tex]

4. Combine the results:
[tex]\[
\text{Total mass} = 103.5 \times 10^{8}
\][/tex]

5. Express the result in scientific notation:
- Adjust 103.5 to proper scientific notation: [tex]\(1.035 \times 10^2\)[/tex]
- Finally, combine: [tex]\(1.035 \times 10^2 \times 10^8 = 1.035 \times 10^{10}\)[/tex]

Therefore, the total mass of the sand on the beach is [tex]\(1.035 \times 10^{10}\)[/tex] grams.