Question

Consider the following reaction:
2Na + Cl2  2NaCl ΔH = -821.8 kJ
(a) Is the reaction exothermic or endothermic? (b) Calculate the amount of heat transferred when
5.6 g of Na reacts at constant pressure. (c) How many grams of NaCl are produced during an
enthalpy change of 16.5 kJ? (d) How many kilojoules of heat are absorbed when 44.1 g of NaCl
is decomposed into Na and Cl2 at constant pressure?
a.
dH is -. By definition that is exothermic.

b.
You get 821.8 kJ for 2*23 or 46 g Na. So 5.6 g Na will give you
821..8 kJ x 5.6/46 = ? kJ.

c.
Rearrange part b. You have 821.8 kJ when 2*58.5 g NaCl are formed.
So 2*58.5 g NaCl x 16.5 kJ/821.8 kJ = ?

d.
See b and c parts.

Post your work if you get stuck.

Related Questions

For the reaction 2Na(s)+Cl2(g)→2NaCl(s)2Na(s)+Cl2(g)→2NaCl(s), how many grams of NaCl could be pro... CaCl2+Na2SO4---> CaSO4+ 2NaCl A. Decomposition reaction B. Double Replacement reaction C. combu... Which of the following is an example of a double replacement reaction?(2 points) Responses C + O...