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how many moles are contained in 8.65 x 10²² atoms of silver? include the units, but do not write the chemical formula.
round the answer to 3 significant figures.
answer:

Explanation:

Step1: Recall Avogadro's number

Avogadro's number is \( 6.022 \times 10^{23} \) atoms/mol, which means 1 mole of any substance contains \( 6.022 \times 10^{23} \) atoms.

Step2: Use the conversion formula

To find the number of moles (\( n \)), we use the formula \( n=\frac{\text{number of atoms}}{\text{Avogadro's number}} \).
Substitute the given number of atoms (\( 8.65 \times 10^{22} \) atoms) and Avogadro's number (\( 6.022 \times 10^{23} \) atoms/mol) into the formula:
\( n=\frac{8.65 \times 10^{22}}{6.022 \times 10^{23}} \)

Step3: Perform the calculation

First, divide the coefficients: \( \frac{8.65}{6.022}\approx1.436 \)
Then, divide the powers of 10: \( \frac{10^{22}}{10^{23}} = 10^{-1}=0.1 \)
Multiply these results: \( 1.436\times0.1 = 0.1436 \)

Step4: Round to 3 significant figures

Rounding \( 0.1436 \) to 3 significant figures gives \( 0.144 \) (or \( 1.44\times 10^{-1} \)) with units of moles.

Answer:

\( 0.144 \) moles