200 mL of a 4 % (w/v) NaOH solution is diluted up to 500 mL. Find the resultant molarity of the solution.
A
0.4 M
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
0.5 M
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
0.8 M
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
0.3 M
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is A 0.4 M 4% (w/v) solution means 4 g of NaOH is present in 100 mL of the solution. Number of moles ofNaOH=given mass ofNaOHmolar mass =440=0.1
Molarity=number of moles of solutevolume of solution in mL×1000
Molarity=0.1100×1000=1M
Conserving moles before and after dilution: M1V1=M2V2
Where, M1=1M and V1=200mL M2 and V2 are the molarity and volume of the resultant solution. (1×200)=(M×500) M=0.4M