# Chemistry

Calculate the standard enthalpy of reaction for the reaction 2Na + 2H2O——> 2NaOH+ H2. Standard enthalpies of formation are -285.8 kJ/mol for H2O and -470.11 kJ/mol for NaOH.

1. 👍 0
2. 👎 0
3. 👁 627
1. Enthalpy of reaction can be found by using the sum of enthalpies of products minus the sum of reactants. Remember that the Heat of formation of elements in their standard states is 0 kJ/mol.

[2(-470.110kJ/mol+(0)]-[2(-285.8kJ/mol)+2(0)]= ?

1. 👍 1
2. 👎 0
2. Right right, thank you so much. It's been a long day so my brain was in a bit of a mushy state. Thanks again!

1. 👍 0
2. 👎 0
3. eqn 1.....H2 + 1/2 O2 ==> H2O dH = -285.8 kJ/mol
eqn 2.....Na + 1/2 O2 + 1/2 H2 ==> NaOH dH = -470.11
--------------------------------------------------------------------
Multiply the reverse of equn 1 by 2 and add to twice eqn 2. Remember to change the sign of dH when a rxn is reversed. Add the two dH values.
Post your work if you get stuck. Check to make sure the equation at the end of the one you want.

1. 👍 0
2. 👎 0
👨‍🏫
DrBob222

## Similar Questions

1. ### Chemistry

Given H2(g) + (1/2)O2(g) --> H2O, ∆Hº = -286 kJ/mol, determine the standard enthalpy change for the reaction 2H2O(l) --> 2H2(g) + O2(g). Just checking... should end up with ∆Hº = 572 kJ/mol right??

2. ### Chemistry

Calculate the standard entropy, ΔS°rxn, of the following reaction at 25.0 °C using the data in this table. The standard enthalpy of the reaction, ΔH°rxn, is –44.2 kJ·mol–1. C2H4(G)+H20 ---> C5H5OH ΔS°rxn= ______

3. ### chemistry

2.9 The standard enthalpy of formation of the metallocene bis(benzene)chromium was measured in a calorimeter. It was found for the reaction Cr(C6H6)2(s) → Cr(s) + 2 C6H6(g) that . Find the corresponding reaction enthalpy and

4. ### Chem

For the reaction, 3C2H2(g) ===> C6H6 at 25°C, the standard enthalpy change is -631 kJ and the standard entropy change is -430 J/K, Calculate the standard free energy change (in kJ) at 25°C. What is the formula that relates

1. ### Chemistry

Given H2(g) + (1/2)O2(g) ---> H2O(l), dH = -286 kJ/mol, determine the standard enthalpy change for the reaction 2h2O(l) ---> 2H2(g) + O2(g) 2H2O(l) ---> 2H2(g) + O2(g) H2(g) + (1/2) O29g) ---> H2O (l) : dH = -286 kJ/mols 2H2O(l)

2. ### chemistry

Calculate the standard enthalpy change for the reaction OF2 (g) + H2O (l) → O2 (g) + 2HF (g). Standard enthalpies of OF2, H2O, and HF are 20 kJ mol-1, -285 kJ mol-1, and -270 kJ mol-1 respectively.

3. ### Chemistry-Enthalpies of formation

"Synthesis gas" is a mixture of carbon monoxide and hydrogen that is used to synthesize a variety of organic compounds. One reaction for producing synthesis gas is 3CH4 + 2H2O + CO2 = 4CO + 8H2 Using enthalpies of formation,

4. ### chemistry

(AAAAA)The standard reduction potentials of lithium metal and chlorine gas are as follows: (for Li, reduction potential is -3.04, for Cl it is 1.36) In a galvanic cell, the two half-reactions combine to 2Li{+](s) + Cl{-}2(g) -->

calculate enthalpy of H for the reaction N2H4(l) + 2H2O(l) -> N2(g) + 4H2)(l) Given the reactions N2H4(l) + O2(g) -> N2(g) + 2H2O(l) Enthalpy of H = -6.22.2 kJ H2(g) + (1/2)O2(g) -> H2O(l) enthalpy of H = -285.8 kJ/mol H2(g) +

2. ### Chemistry

Propane (C3H8) burns according to the following balanced equation: C3H8(g)+5O2(g)→3CO2(g)+4H2O(g) Calculate ΔH∘rxn for this reaction using standard enthalpies of formation. (The standard enthalpy of formation of gaseous

3. ### chemistry

for the reaction 3C2H2=> C6H6 at 25 C, the standard enthalpy change is -631 KJ and the standard entropy change is -430 J/K. calculate the standard free energy change at 25 C. show all work!

4. ### chemistry

use standard enthalpies of formation to calculate delta Hrxn for the following reaction. 2H2S(g)+3O2(g)-->2H2O(l)+2SO2(g) express the answer using four significant figures Delta Hrxn = ? kJ