# Science

posted by Meena

IF 8.5g of KOH powder are placed in 100g of water at room temperature of 20degree Celsius, what is the final temperature of the solution.
KOH K+OH H=-57.61 KJ/MOL KOH

1. bobpursley

if the heat of solution is -57.62kj per mole, the question is what portion of a mole is 8.5 grams?
8.5/56.1=...
Now the sum of heats gained is zero.
8.5/56.1*57.64+100g* 4.18kj/kg*(tf-20)=0

tf-20= 8.7/.418

solve for temp final tf. Check my work

2. Sunny

when calculating the heat gained by solution, the total mass will be 108.5 gm not 100gm. Since there was 8.5g of KOH added to water.

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