How many grams of antifreeze c2h4(oh)2 would be required per 500 g of water to prevent the water from freezing at a temperature of -20.0 c

333.7 g.

Explanation:

Where, ΔTf is the depression in water freezing point (ΔTf = 20.0°C).

Kf is the molal freezing point depression constant of the solvent (Kf = 1.86 °C/m).

m is the molality of the solution.

∴ m = ΔTf/Kf = (20.0°C)/(1.86 °C/m) = 10.75 m.

molaity (m) is the no. of moles of solute per kg of the solvent.

∵ m = (no. of moles of antifreeze C₂H₄(OH)₂)/(mass of water (kg))

∴ no. of moles of antifreeze C₂H₄(OH)₂ = (m)(mass of water (kg)) = (10.75 m)(0.5 kg) = 5.376 mol.

∵ no. of moles = mass/molar mass.

∴ mass of antifreeze C₂H₄(OH)₂ = no. of moles x molar mass = (5.376 mol)(62.07 g/mol) = 333.7 g.

"the periodic table is arranged in order of atomic number."

i think it's letter a.