4.5g of compound A(MW=90) was used to make 250mL of its aqueous solution. The molarity of the solution in M is x×10−1. The value of x is ......... (Rounded off to the nearest integer).
Given, weight of compound A=4.5g Molecular weight of compound A=90g∕mol Volume of solution (in mL ) =250mL Now, molarity is defined as number of moles of solute or compound A divided by volume of solution (in L). M‌‌=‌
‌ Number of moles of solute ‌(n)
‌ Volume of solution ‌
‌‌=‌
‌
4.5
90
250
1000
=0.2‌ or ‌=2×10−1M ∴‌‌n‌‌=‌
‌ Weight of solute (compound ‌A‌ ) ‌
‌ Molecular weight of solute (compound ‌A‌ ) ‌