200 g and 5% baking soda solution must be prepared. How much soda (in grams) and how much water (in milliliters) will be needed?

190 mL of water

Explanation:

5% solution means that 5 g of substance in 100 g of solution.

So, if we have 5 g of substance, and it has to be 100 g solution, than we need 100-5 = 95 g water.

100 g solution - - - 5 g soda-- - 95 g water

200g solution - - - 10 g soda - --190 g water

For 200 g of 5% solution, we will need 10 g of soda and 200-10 = 190 g of water.

Density of water = 1 g/mL

190 g * 1ml/g = 190 ml water