To find out the mass fraction of the salt used in the resulting solution, we apply the formula: ωc = mc / mr-pa * 100% = mc / (mH2O + mc) * 100%, where mc is the mass of the salt used (mc = 30 g); mH2O is the mass of consumed water (mH2O = 170 g).
Let’s calculate: ωс = mс / (mН2О + mс) * 100% = 30 / (170 + 30) * 100% = 15%.
Answer: In the solution, the mass fraction of the salt used is 15%.
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