Question

the average human body contains 32.4 moles of calcium, 99% of which is found in bones and teeth.
how many atoms of calcium are in the average human body?
express your answer in scientific notation with two decimal places.
show avogadros number
atoms of calcium

Explanation:

Step1: Recall Avogadro's Number

Avogadro's number is \( 6.022 \times 10^{23} \) atoms/mol. We need to find the number of atoms in 32.4 moles of calcium.

Step2: Use the formula \( \text{Number of atoms} = \text{Moles} \times \text{Avogadro's Number} \)

Substitute the values: \( \text{Number of atoms} = 32.4 \, \text{mol} \times 6.022 \times 10^{23} \, \text{atoms/mol} \)
Calculate the product: \( 32.4 \times 6.022 = 195.1128 \)
So, \( \text{Number of atoms} = 195.1128 \times 10^{23} \)
Convert to scientific notation: \( 1.951128 \times 10^{25} \)
Round to two decimal places: \( 1.95 \times 10^{25} \)

Answer:

\( 1.95 \times 10^{25} \)