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3 years ago

How much water needs to be added

Chemistry

1 answer:

Olegator [25]3 years ago

8 0

Answer:

165 ml

Explanation:

We are given;

Initial volume; V_a = 55 ml

Initial molarity; M_a = 3 M

Molarity of desired solution; M_b = 0.75 M

Volume of desired solution; V_b = (55 + x) ml

Where x is the volume of water to be added.

To solve for V_b, we will use the equation ;

M_a•V_a = M_b•V_b

V_b = (M_a•V_a)/M_b

V_b = (3 × 55)/0.75

V_b = 220 mL

Thus;

(55 + x) = 220

x = 220 - 55

x = 165 mL

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Answer:

10.23 grams of sucrose should be added.

Explanation:

1.15 m means molality (moles of solute in 1kg of solvent)

1.15 moles of sucrose are contained in 1 kg of solvent (1000 g)

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Answer:

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