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3 years ago

How many mL of a stock 50% (w/v) KNO3 solution are needed to prepare 250 mL of a 20% (w/v) KNO3 solution?

Chemistry

1 answer:

Andre45 [30]3 years ago

6 0

Answer:

100ml of a stock 50% KNO3 solutions are needed to prepare 250ml of a 20% KNO3 solution.

Explanation:

In the given question it is mentioned that

S1=50%

V2=250ml

S2= 20%

We all know that

V1S1=V2S2

∴V1= V2×S2÷S1

∴V1= V2S2×1/S1

∴V1= 250×20÷50

∴V1= 100ml

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Explanation:

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3 years ago

The less energy a wave has, the greater its amplitude. True or False

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Answer:

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