Question

AH = -q/moles ITA Calcium Grams Mole 1.070 .027 1.024 .026 Data and Observations (10pts) Temperature Grams q = 4.18 x ATX m T AT Water (m = mass of Water) 19.5 40. 9 2 1.4 100 19.6 41.1 21.5 100 Average AH Trial 1 Trial 2 1. (2pts) Balance the chemical equation of calcium with water to produce calcium hydroxide and hydrogen gas. Ca2+ (s) + 2 H20 (1) ► CaļOH)2 (@g) + H2 (g) 2. (12pts) List the reference values for 4G, and sº of each reaction component and calculate AG and Schevenica, for the reaction. Using AG oo and the average of the experimentally determined value for AH in this experiment, report semi-experimental value for AS (assume standard temperature). Compare this value to the theoretical value (Schwerpu) and calculate a percent error. What would cause any variance? (You must show your calculations.) 4G (kJ/mol) Sº (J/mol*K) Reaction Component Ca(s) H2O(0) Ca(OH)2(s) H2(g)

need help with the top table (blank two)

and #2

Answer 1

(1) As we know

Energy change (q) = $ms\Delta t$

where, m = mass of water in grams, s = specific heat capacity water (4.18 $Jgm^{-1}K^{-1}$ ), $\Delta t$ = change in temperature in K.

$\Delta H =-q/n$, where q is energy change and n is number of mole.

Here $\Delta H$ represents the energy change to from Ca(OH)2 from 1 mole Ca

So in trial 1

q=100*4.18*21.4 J = 8945.2 J = 8.9 kJ

$\Delta H$ = -8.9 kJ/ 0.027 mole = -329.63 kJ/mole

In trial 2

q = 100*4.18*21.5 J = 8987 J = 8.99 kJ

$\Delta H$ = -8.99 kJ/ 0.026 mole = -345.77 kJ/mole