# Chemistry!

When 2.5g of NaOH were dissolved in 49.0g water in a calorimeter at 24.0 C, the temperature of the solution went up to 37.1 C.

a. Is the solution reaction exothermic?
Why? The temperature or the water went from 24.0 to 37.1 which is an increase. If the solution of NaOH in water made the temperature of the water go up, do you think the NaOH + H2O gave off heat (exothermic) or took in heat (endothermic)?

b. Calculate q h2o, using eq. 1. Its tough to know what you did when you don't supply equation 1.
c. Find delta H for the reaction as it occured in the calorimeter (eq. 5).See comment to part b.
d. Find delta H for the solution of 1.00g NaOH in water. The delta H you found was for 2.5g. What would it be for 1.0g?
Find delta H for the solution of 1 mole NaOH in water. The delta H you found for part d was for 1.0g. A mol of NaOH is 40g. Just convert from 1.0g to 40g.
f. given that NaOH exists as Na+ and OH- ions in solution, write the equation for the reaction that occurs when NaOH is dissolved in water. NaOH(s) ==> Na+(aq) + OH-(aq) + heat
g. Using ethalpies of formation as given in thermodynamic tables, calculate delta H for the reaction in part f and compare your answer with the result obtained in Part e. You must look up the delta Hf.

Please explain how to do. All of this is new to me. Thank you so much!

When 2.5g of NaOH were dissolved in 49.0g water in a calorimeter at 24.0 C, the temperature of the solution went up to 37.1 C.

a. Is the solution reaction exothermic?
Why?

b. Calculate q h2o, using eq. 1.
c. Find delta H for the reaction as it occured in the calorimeter (eq. 5).
d. Find delta H for the solution of 1.00g NaOH in water.
Find delta H for the solution of 1 mole NaOH in water.
f. given that NaOH exists as Na+ and OH- ions in solution, write the equation for the reaction that occurs when NaOH is dissolved in water.
g. Using ethalpies of formation as given in thermodynamic tables, calculate delta H for the reaction in part f and compare your answer with the result obtained in Part e.

1. 👍 0
2. 👎 0
3. 👁 971

## Similar Questions

1. ### science

C respectively to prepare a 50% (mass by volume) solution of sodium hydroxide (NaOH). 'A' dissolved 50 g of NaOH in 100 ml of water B dissolved 50g of NaOH in 100g of water while C dissolved 50g of NaOH in water to make 100ml of

asked by akshay on August 12, 2015
2. ### science

the teacher instructed three students A,B,and C respectively to prepare a 50% (mass by volume) solution of sodium hydroxide (NaOH). 'A' dissolved 50 g of NaOH in 100 ml of water B dissolved 50g of NaOH in 100g of water while C

asked by irsha on September 6, 2011
3. ### science

the teacher instructed three students A,B,and C respectively to prepare a 50% (mass by volume) solution of sodium hydroxide (NaOH). 'A' dissolved 50 g of NaOH in 100 ml of water B dissolved 50g of NaOH in 100g of water while C

asked by chemistry on September 6, 2011
4. ### Chemistry

when 2g of NaOH were dissolved in 149 g of H2o in a calorimeter at 24 degrees C the temperature of the solution went up to 29 degrees C. If the calorimeter constant was 11 cal/C find delta H for the solution of one mole of NaOH in

asked by Dexter on October 19, 2014
5. ### Chemistry - Heat Capacity

When a 3.25 g sample of solid sodium hydroxide was dissolved in a calorimeter in 100 g of water, the temperature rose from 23.9 C to 32.0 C. Calculate delta H (in kJ/mol) of for the solution process: NaOH (s) -> Na+(aq) + OH-(aq)

asked by Amy on December 17, 2012
6. ### Heat Capacity

When a 3.25 g sample of solid sodium hydroxide was dissolved in a calorimeter in 100 g of water, the temperature rose from 23.9 C to 32.0 C. Calculate delta H (in kJ/mol) of for the solution process: NaOH (s) -> Na+(aq) + OH-(aq)

asked by Jamie on December 18, 2012
7. ### Chemistry

when pure sodium hydroxide is dissolved in water , heat is evolved in a laboratory experiment measure a molar heat of solution of sodium hydroxide the following procedure was followed. to a calorimeter containing 300g of water at

asked by jim on March 23, 2007
8. ### Chemistry Help(Calorimetry)

I have a few questions to ask, since I was absent from school and I do not really understand the calorimetry problems. 1) When a 16.9 g sample of NaOH dissolves in 70.0 g of water in a calorimeter, the temperature rises from

asked by Bonn on April 9, 2010
9. ### AP Chemistry

Determine the pH of the following solutions. 1) 0.600 M HCl 2) 0.052 moles of H2SO4 dissolved in 4.2 L of water. 3)5.6 grams HNO3 dissolved in 450 ml of water. 4) 2.5 grams of NaOH dissolved in 500 mL of water. 5) adding 2 grams

asked by Tyra on February 19, 2016
10. ### AP Chemistry

Determine the pH of the following solutions. 1) 0.600 M HCl 2) 0.052 moles of H2SO4 dissolved in 4.2 L of water. 3)5.6 grams HNO3 dissolved in 450 ml of water. 4) 2.5 grams of NaOH dissolved in 500 mL of water. 5) adding 2 grams

asked by Tyra on February 20, 2016

More Similar Questions