Answer
B. 6.02 x 10²³ molecules CH₄
Explanation
Avogardro's constant says 1 mole of a substance has 6.02 x 10²³ molecules.
⇒ 1 mole = 6.02 x 10²³ molecules/atoms
Therefore, the mole of methane in the given molecules can be calculatedas follows
[tex]Mole\text{ of methane }=\frac{7.31\times10^{25}_{}}{6.02\times10^{23}\text{ }molecules\text{ }CH_4}=121.43\text{ mole}[/tex]
Hence, what belongs to the green box is 6.02 x 10²³ molecules CH₄
