# chemistry - Molar enthalpy

posted by .

When 10.0 g of KOH is added to 100.0 g water, the solution's temperature increases from (25.18 C) to (47.53 C). What is the molar enthalpy of solution for KOH?

i tryed

q=(m)x(c)x(delta T)

didn't really work. i got 22.35 J

do i use that to find the molar enthalpy if so how?

• chemistry - Molar enthalpy -

No, that's not what you obtained. I know it isn't. 22.35 = Tfinal - Tinitial = 47.53-25.18 = 22.35 and that doesn't come close to m x c x delta T.

• chemistry - Molar enthalpy -

haha, yep,

ok so q= 10,276.53 J

and to get the answer in molar enthalpy should i divide q by the mole of KOH

10.0g KOH (1 mol KOH/ 56.105g) = 0.1782 mol KOH

10,276.53 J / 0.1782 mol KOH = 57,668.5J/mol

= 57.6 kJ/mol

Is this right?

• chemistry - Molar enthalpy -

and would the answer be positive because the temperature is increased?

• chemistry - Molar enthalpy -

Close but no cigar.
You had better redo the q part. I think it's closer to 9300 J or so. The rest of it is as you have it. q/mols KOH = J/mol but it usually is reported in kJ/mol.

## Similar Questions

1. ### Chemistry

"Translate the empirical molar enthalpy given below into a balanced chemical equation, including the enthalpy change (delta H): The standard molar enthalpy of formation for carbon disulfide is 89.0 kJ/mol" I got delta H = 178 kJ (is …
2. ### college chemistry

Consider the titration of a 50.0 mL sample of a 0.100 M solution of the triprotic weak acid citric acid (H3C6H5O7) with 0.100 M KOH. For citric acid, the three (3) acid dissociation constant values are ka1 = 7.40x10-3, ka2 = 1.70x10-5, …
3. ### Chemistry

A calorimeter contains 21.0 mL of water at 14.0 degreesC. When 1.90 g of X (a substance with a molar mass of 70.0 g/mol) is added, it dissolves via the reaction X(s)+H_2O(l)reacts to make X(aq) and the temperature of the solution increases …

A 65.0 g sample of 0.600 M HI at 18.46 degrees celsius is added to 84.0 g of solution containing excess KOH, also at 18.46 degrees celsius. The final temperature is 21.96 degrees celsius. Calculate the enthalpy of H for the reaction. …
5. ### Chemistry

when 5.0g of KOH is added to 100mL, of water, the temperature of the solution increases by 3 degrees celsius. Assume the density of the solution to be 1g/mL and specific heat capacity of the solution to be 4.184 J/g K. a. calculate …
6. ### Chemistry

A calorimeter contains 22.0 mL of water at 14.0 C. When 2.50 g of X (a substance with a molar mass of 66.0 g/mol) is added, it dissolves via the reaction X(s)+H_2O(l)--------> X(aq) and the temperature of the solution increases …
7. ### chem

a.)How many moles of NaOH are required to prepare 2.00L od 0.380M solution?
8. ### ap chemistry

A calorimeter contains 20.0 of water at 12.5 . When 2.20 of (a substance with a molar mass of 59.0 ) is added, it dissolves via the reaction and the temperature of the solution increases to 27.5 . Calculate the enthalpy change, , for …
9. ### Chemistry-DrBob222

I know I pored this already, but I for it to mention the assumption. See below. A calorimeter contains 30.0 mL of water at 15.0 C. When 1.50 g of X (a substance with a molar mas of 46.0g/ mol is added, it dissolves via the reaction …
10. ### Chemistry

Hello, I was wondering what would happen if u add KOH(potassium hydroxide) solution instead of KOH solid to HCL (hydrochloric acid). Currently, learning enthalpy in class and I'm not sure how this affects enthalpy

More Similar Questions