Answer:
We have 1.13 * 10^24 molecules in 30.0 grams CH4 (option C)
Explanation:
Step 1: Data given
Mass of CH4 = 30.0 grams
atomic mass C = 12.00 g/mol
atomic mass H = 1.01 g/mol
Step 2: Calculate molar mass CH4
Molar mass CH4 = 12 + 4*1.01 g/mol
Molar mass CH4 = 16.04 g/mol
Step 3: Calculate moles CH4
Moles CH4 = mass CH4 / molar mass CH4
Moles CH4 = 30.0 grams / 16.04 g/mol
Moles CH4 = 1.87 moles
Step 4: Calculate number of molecules
number of molecules =moles * number of Avogadro
number of molecules = 1.87 * 6.022 * 10^23 / moles
number of molecules = 1.13 * 10^24 molecules
We have 1.13 * 10^24 molecules in 30.0 grams CH4 (option C)
