What’s the answer please gelp

Option A. 1.8×10²⁴ molecules.

Explanation:

Data obtained from the question include:

Number of mole of methane = 3 moles

Number of molecules of methane =?

From Avogadro's hypothesis, we understood that 1 mole of any substance contains 6.02×10²³ molecules.

Thus, 1 mole of methane equally contains 6.02×10²³ molecules.

With the above information in mind, we can obtain the number of molecules in 3 moles of methane as follow:

1 mole of methane contains 6.02×10²³ molecules.

Therefore, 3 moles of methane will contain = 3 × 6.02×10²³ = 1.8×10²⁴ molecules.

Thus, 3 moles of methane contains 1.8×10²⁴ molecules.

a electronegativity decreases beacuse the size of nucleus is bigger.

the answer is 75.0%.