Explain the enthalpies of formation of elements

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In an experiment Temperature of Hydrochloric acid (HCl=1.020M) solution is 23.4 degrees celcius. The temperature of sodium hydroxide solution (NaOH = .907M) is also 23.4 degrees celcius. When 50mL of each are mixed together the final temperature is 29.2 degrees celcius.

a. q=mcΔT Insert your values and calculate q for your solution.

b. Calculate enthalpy of neutralization

i. qrxn= -qsoln

ii. Mole of NaOH or HCL neutralized (moles of reaction)

iii. Enthalpy of neutralization of reaction = qrxn/(moles of reaction)

c. Enthalpies are relative quantities measured as changes from some comparative states. The enthalpies of formation of elements in their standard states at 25 degrees celcius are taken to be zero by convention. The enthalpy of formation of a 1M solution of H+ (aq) is chosen by definition to be zero. Look up enthalpy of formation of H2O(l)..using that value and your results from the experiment calculate enthalpy of formation of OH- (aq).

Reference no: EM13503551

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