Methane and chlorine react to form chloromethane, CH3Cl and hydrogen chloride. When 29.8 g of methane and 40.3 g of chlorine gas undergo a reaction that has a 64.7% yield, how many grams of chloromethane form

18.26g

Explanation:

Equation of reaction;

CH₄ + Cl₂ → HCL + CH₃Cl

mass of CH₄ = 29.8g

molar mass of CH₄ = 16g/mol

mass of Cl₂ = 40g

molar mass of Cl₂ = (35.5*2) = 71g/mol

molar mass of CH₃Cl = 50.46g/mol

no. of moles = mass / molar mass

no. of moles of CH₄ = 29.8 / 16 = 1.8625 moles

no. of moles of Cl₂ = 40 / 71 = 0.56moles

Note : limiting reactant is Cl₂

From equation of reaction,

1 mole of Cl₂ = 1 mole of CH₃Cl

0.56 moles of Cl₂ = 0.56 moles of CH₃Cl

No. Of moles of experimental yield = no. Of moles of theoretical yield * percentage yield.

Theoretical yield of n(CH₃Cl) = 0.56 moles

n(CH₃Cl exp) = 0.56 * 0.647

n(CH₃Cl exp) = 0.36232 moles

Number of moles = mass / molar mass

Mass = no. Of moles * molar mass

Mass = 0.36232 * 50.46 = 18.26g

m(CH₃Cl) = 18.26g

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.