Find %(w/v) from ppm?

Question

I have 95 ppm Ca^2+ in water. Assume the density of soln is the same as pure water. What is its % (w/v) Ca^2+?

Answer 1

Percentage (%) is the same as parts per hundred. PPM is parts per million so there is a direct mathematical formula.

% = PPM / 10,000 so 95 PPM = 0.0095%

Answer 2

When the density is the same as water, ppm=mg/l. This is what allows you to convert to w/v (which I assume is weight over volume)