To make 250 ml of a 5%(w/v) calcium carbonate solution, how many grams of calcium carbonate will I need?

You can go about this two ways.

(g solute/ mL)*100 = %
(g CaCO3/250 mL)*100 = 5%
Solve for g CaCO3.

The other way is that 5% w/v means 5g CaCO3 in 100 mL, you want 250 so
5g CaCO3 x (250/100) = g needed for 250 mL instead of 100 mL.

By the way I don't think this is possible because CaCO3 is not all that soluble.

I believe it's hypothetical. Just some simple review for my finals and this one slipped my mind. Thank you so much. 12.5g is needed for 250mL

To find out how many grams of calcium carbonate you will need to make a 5% (w/v) solution, we first need to understand what a 5% (w/v) solution means.

"W/v" stands for weight/volume, which is a concentration unit commonly used in chemistry. It represents the weight of a solute (in this case, calcium carbonate) dissolved in a given volume of solvent (in this case, water).

To calculate the amount of calcium carbonate needed, we can use the following formula:

Mass of solute = (Percentage concentration / 100) x Volume of solution

In this case, the percentage concentration is 5%, and the volume of solution is 250 ml.

Plugging those values into the formula, we get:

Mass of calcium carbonate = (5 / 100) x 250 ml

Mass of calcium carbonate = 0.05 x 250 ml

Mass of calcium carbonate = 12.5 grams

Therefore, you will need 12.5 grams of calcium carbonate to make a 250 ml 5% (w/v) calcium carbonate solution.