Answer:
![\begin{gathered} a)\text{atoms of }C=4.29*10^(24)atoms \\ b)\text{ 85.56g} \end{gathered}](https://img.qammunity.org/2023/formulas/chemistry/college/qhkxixtrku2rbgt06c2nt3bwk1vma9ld3w.png)
Explanations:
a) Given the following parameter from the question
Mole of carbon-12 = 7.13 moles
Using the conversion rate
1 mole = 6.02 * 10²³ atoms
Determine the atoms of carbon-12:
![\begin{gathered} \text{atoms of }C=7.13*6.02*10^(23)\text{ atoms} \\ \text{atoms of }C=42.9226*10^(23)atoms \\ \text{atoms of }C=4.29*10^(24)atoms \end{gathered}](https://img.qammunity.org/2023/formulas/chemistry/college/4trrac2didv8kzrw8ofb7tlxwtayuwu98c.png)
b) In order to determine the grams of carbon-12, the expression below will be used:
![\begin{gathered} \text{Mass}=\text{Mole}*\text{molar mass} \\ \text{Mass of C=7.13moles}*(12g)/(mol) \\ \text{Mass of C=}85.56grams \end{gathered}](https://img.qammunity.org/2023/formulas/chemistry/college/5fea5ktmhsctai4zhw18vuaq5e9hdxaz7b.png)
Hence the number of grams the carbon-12 weigh is 85.56 grams