Question

20 ml of 0.1 M, 30 ml of 0.2 M and 30 ml of 0.3 M solutions of oxalic acid are mixed and the volume is made 100 ml. The molarity of the resulting solution is

0.21 M
8.51 M
5.67 M
0.17 M

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Answer 1

Answer:

The correct answer is 0.21M.

Explanation:

To find the molarity of the resulting solution:

$Molarity = \frac{M_{1}V_{1} + M_{2}V_{2} }{V_{1}+V_{2} }$

The molarity of the first compound is- 0.1M

The volume of the first compound is- 20ml

The molarity of the second compound is- 0.2M

The volume of the second compound is- 30ml

The molarity of the third compound is- 0.3M

The volume of the third compound is- 30ml

$Molarity = \frac{(0.1*20)+(0.2*30)+(0.3*30)}{20+30+30}$

$Molarity = \frac{17}{80} = 0.21M$

Conclusion:

The molarity of the resulting solution is 0.21 M.

Answer 2

Answer:

0.17M

Explanation:

when we are given different concentrate of same substance... we apply the formula

M1V1 + M2V2+.....MnVn = MrVr

(R = resultant solution)

so the equation will be

[(0.1×20)+(0.2×30)+(0.3×30)] = 2+6+9 = 17

MrVr= 17

but the volume is made 100ml

so Vr = 100

Mr = 17/100

therefore Molarity of the solution is 0.17M