What is the percent by mass of solute if 14.60g 74.95g of water?

16.30 %

In this case;

Mass of solute = 14.60 g

Mass of solvent = 74.95 g

But, Mass of solution = mass of solute + mass of solvent

Thus;

Mass of solution = 14.60 g + 74.95 g

                           = 89.55 g

Therefore;

% mass = (14.60 ÷ 89.55 g) × 100%

            = 16.30 %

Hence, the mass percent is 16.30%

percent abundance for cu-63 can be shown as:

63 x + 65 (1-x) = 62.9296

65 - 62.9296 = 2 x

x = 1.035

thus, percent abundance for cu-63 is 1.035

percent abundance for cu-65 can be shown as:

63 x + 65 (1-x) = 64.9278

65 - 64.9278 = 2 x

x = 0.0361

thus, percent abundance for cu-63 is 0.0361

the mass spectrum of cu-63 showing the intense peak as, this isotope is found in nature more abundantly around 92.38 % in comparison to cu-65 which is found 62.58 % naturally