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Dear BAMxTiFFANY;Nearly correct!, - but you forgot the units!Now we know that 1.050 kg solution contains 73.05 g sodium chloride. a.) How much grams are left for water? b.) And what’s then the molality?Good Luck! ARGOS^{++}

Dear BAMxTiFFANY;The weight of water is correct!But then you are toooo fast and that’s why it is not correct: 73.05g are not 0.07305 moles! !!!!!! Please calculate all times with units !!!!!!! So remember: 73.05g are 1.25 moles sodium chloride! So what’s now the result for b.)?Good Luck! ARGOS^{++}

Dear BAMxTiFFANY;Bravo!, - That’s exact!And now: c.) How many moles are this 976.95g water? d.) What’s now the mole fraction?Good Luck! ARGOS^{++}

Dear BAMxTiFFANY;C.) is correct!For d.) remember its definition! – mole-fraction is unit-less! So you have not to multiply be 100!Can you do d.) once again?Good Luck! ARGOS^{++}

Dear BAMxTiFFANY;Exact!Now can you finally calculate the % w/w of the solution?Good Luck! ARGOS^{++}

Dear BAMxTiFFANY;Sorry!, % w/w has nothing to do with mole-fraction!Please use the definition of % w/w!Good Luck! ARGOS^{++}

Dear BAMxTiFFANY;That’s not correct!, - w/w = weight/weight has nothing to do with moles too.Good Luck! ARGOS^{++}