[tex]0.68 \: moles \: calcium \times \frac{6.02 \times {10}^{23} \: calcium \: atoms }{1 \: mole \: calcium} \\ [/tex]
The (( mole calcium ))s are simplified so the answer is based on the number of calcium atoms.
[tex]0.68 \times 6.02 \times {10}^{23} = 68 \times {10}^{ - 2} \times 602 \times {10}^{ - 2} \times {10}^{23} \\ [/tex]
[tex] = 68 \times 602 \times {10}^{ - 4} \times {10}^{23} = 40936 \times {10}^{19} \\ [/tex]
[tex] calcium \: atoms = 40936 \times {10}^{19} \\ [/tex]
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And we're done.
Thanks for watching buddy good luck.
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