What is molarity of K in aqueous solution that contains 17.4 ppm of P...
17.4 ppm means 17.4 mg/litre. So first convrt it into gm = 17.4�10^-3 gm/litre.
Nw to find molarity =w(solute in gm)/mwt of solute�solution in litre.
=17.4�10^-3/174�1 =10^-4M
So in k2so4 k+ it will brk as 2 K+ therefore molarity=2�10^-4 ans.
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What is molarity of K in aqueous solution that contains 17.4 ppm of P...
Solution:
Given, concentration of potassium sulphate = 17.4 ppm
To find molarity of K, we need to convert ppm into molarity.
Step 1:
Find the molar mass of potassium sulphate.
Molar mass of K2SO4 = 2 × atomic mass of K + atomic mass of S + 4 × atomic mass of O
= 2 × 39.1 + 32.1 + 4 × 16.0
= 174.3 g/mol
Step 2:
Calculate the number of moles of potassium sulphate present in 1 L of solution.
Number of moles = concentration (in g/L) ÷ molar mass
Concentration of potassium sulphate in ppm = 17.4 ppm = 17.4 mg/L
Number of moles of K2SO4 in 1 L of solution = 17.4 mg/L ÷ 174.3 g/mol
= 0.0001 mol/L
Step 3:
Calculate the number of moles of potassium ions (K+) present in 1 L of solution.
In 1 mole of K2SO4, there are 2 moles of K+ ions.
Number of moles of K+ ions = 2 × 0.0001 mol/L
= 0.0002 mol/L
Step 4:
Calculate the molarity of K+.
Molarity of K+ = Number of moles of K+ ions ÷ Volume of solution in L
= 0.0002 mol/L
Therefore, the molarity of K in the given solution is 0.0002 M or 0.2 mM.
Answer: Option (a) 0.0002
What is molarity of K in aqueous solution that contains 17.4 ppm of P...
0.0002