From a 95% ethanol (ETOH) stock solution, you need to make 250 mL of 70% ETOH....

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Question

Answer 1

Answer #1

1.ans C1V1=C2V2, 70 X 250 = 95 X ?, ? = 70 X 250 / 95 = 184.21

so 184.21ml of 95% ethanol will be diluted to 250 ml using distilled water.

2.ans. I hpoe the actual labeling was 80% on the bottle but by mistake we consider it as 95%. and we add 184.21ml of it and diluted to 250ml.

so our new concentration of solution

80 x 184.21 = ? x 250, ? = 80 x 184.21 / 250 = 58.947

so our new concentration is 58.95.

Answer 2

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