58 mL of water and 27 g of sodium chloride were added into the 150 g of 20%
solution of the same salt. Calculate the percentage of sodium chloride in the new
solution.
Answers
Answer:
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Answer:
this te question exactly as given to you ? Is it given by your teacher or did you get it direct from a text book?
I ask this because I am regularly concerned at the poor quality of questions submitted , not only to Quora , but other forums like this. Why am I concerned with what you have submitted?
1) You state 20% solution…. This is meaningless . Unless you specify whether it is 20% m/m . 20% m/v etc - these are different solutions . For simplicity I will take this as a 20%m/m solution .
2) Why are you adding 58 mL of water? Throughout the question you deal with mass units - why now a volume? Or is the questioner expecting the answer to include a conversion from volume to mass - which would then require a temperature specified. I am going to work on the basis that the question reads: 58 g of water and 27 g NaCl …. etc.
Answer:
Mass NaCl in 150 g 20%m/m solution = 20/100%*150 g = 30 g NaCl + 120 g H2O
The final solution will contain 30 g NaCl + 27 g NaCl = 57 g NaCl
and it will contain : 120 g H2O + 58 g H2O = 178 g H2O
Total mass = 57g NaCl + 178 g H2O = 235 g solution
%m/m NaCl in final solution = 57g NaCl / 235 g solution * 100 % = 24.25%