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1 year ago

Calculate the concentration expressed in percent, if 10 g of NaOH is diluted to 500 ml with water.

Chemistry

1 answer:

Zepler [3.9K]1 year ago

5 0

If 10 g of NaOH is diluted to 500 ml with water then the concentration expressed in percent is 0.5 mol/L .

Calculation ,

Given mass in gram = 10 g

Number of moles = given mass /molar mass = 10 g / 40 g/mol = 0.25mole

Given volume in ml = 500 ml

Given volume in liter = 0.5 L

Putting the value of mass and volume in equation i we get concentration expressed in percent .

C = number of moles ×100/ volume in liter = 0.25mole ×100/ 0.5 L

C = 0.5 mol/L

Concentration of solution in terms of percentage can be expressed in two ways

1) percentage by mass

2) percentage by volume

Hence, for liquid solutions, concentration is expressed in terms of percentage by volume.

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