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1. Calculate the number of atoms present in \(1\) gram of gold (atomic mass of \(Au=198\)).
Data:
Given mass of gold \(=1\) \(g\)
Atomic mass of \(Au=198\)
Avogadro's number \(=6.023\times10^{23}\)
Solution:
Number of atoms of \(Au\) \(=\)
Where,
x \(=\)
y \(=\)
Therefore, the number of atoms present in \(1\) gram of gold \(=\) \(z\times10^{21}\) \(g\)
z \(=\)
2. Calculate the number of atoms of oxygen and carbon in \(5\) \(moles\) of \(CO_2\).
Calculating number of oxygen atoms in \(5\) \(moles\) of \(CO_2\):
- \(1\) \(mole\) of \(CO_2\) contains \(2\) \(moles\) of oxygen.
- \(5\) \(moles\) of \(CO_2\) contain \(10\) \(moles\) of oxygen.
Solution:
Number of atoms of \(O_2\) \(=\)
Therefore, the number of atoms of oxygen in \(5\) \(moles\) of \(CO_2=\) \(x\times10^{y}\)
Calculating the number of carbon atoms in \(5\) \(moles\) of \(CO_2\):
- \(1\) \(mole\) of \(CO_2\) contains \(1\) \(moles\) of carbon.
- \(5\) \(moles\) of \(CO_2\) contain \(5\) \(moles\) of carbon.
Number of atoms of \(C\) \(=\)
Therefore, the number of atoms of carbon in \(5\) \(moles\) of \(CO_2=\) \(3.011\times10^{y}\)
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