For #1, what else would you do? Add the CaCl2 to water? I got that you would nee
ID: 477392 • Letter: F
Question
For #1, what else would you do? Add the CaCl2 to water? I got that you would need 22.196g of CaCl2 to make the solution, but what are the "steps?" For #2, is it correct? For #3, I am a little confused. I set it up the way I thought would make sense, but if I work it out, I get 10g, which doesn't seem right. Any help is super appreciated! Practice problems Concentration a. Show the steps to make 200 ml of a 1 M CaCl2 solution (M.W. 110.98) b. How much EDTA disodium dehydrate (Mw 372.2 g/mo) would you need to make 50 ml of 0.25 M EDTA? 2s M EDTA Somb 3120 c. How much EDTA disodium dehydrate would you need to weigh to prepare 100 ul of a 10% EDTA solution? 100Explanation / Answer
1) Molarity = (W/MW) x (1000 / volume of solution in mL)
1.0 M = (W /110.98) (1000 / 200)
200 / 1000 = W/110.98
0.2 = W / 110.98
W = 22.196 g
we should dissolve 22.196 g CaCl2 in 200 mL solution using volumetric flask
2) Molarity = (W /MW) (1000 / volume of solution in mL)
0.25 = (W / 372.2) (1000 / 50)
0.25 x 50 / 1000 = W / 372.2
0.0125 = W/372.2
W = 4.6525.
4.6525 g EDTA we should dissolve in 50 mL water.
3) you must conform weather % is W/ or W/V then only we can proceed
3) % W/V = (mass of solute / volume of solution) x 100
10 = ( W / 0.1) x 100
W = 0.01 g
0.01 g EDTA required