How many grams of cacl2 are needed to make3.5l (3500ml)
of a 15% calcium chloride solution?

525 grams

Explanation:

Assuming the solution to be prepared is 15% by weight calcium chloride, it means 15 grams of calcium chloride will be in 100 mL of solution.

To calculate the amount needed to make 3500 mL solution;

15 g is required to make 100 mL

X g is required to make 3500 mL

X = 15 x 3500/100

          = 525 g

Therefore, 525 grams of calcium chloride will be needed to make 15%, 3500 mL of calcium chloride solution.

format change of dna.  

oxygen +1 most likely