Question

1. Write balanced thermochemical (remember to include calculated enthalpy changes) reaction equations for: a. The single replacement reaction between magnesium and hydro- chloric acid. Label it reaction I. b. The double replacement reaction between magnesium oxide and hydrochloric acid. Label it reaction II. c. The formation of water. Label it reaction III. d. The formation of magnesium oxide. Label it reaction IV. 2. Demonstrate that reactions I, II, and III, can be added (after appropriate manipulations) to yield reaction IV. 3. Find and record values for Ahºf for magnesium oxide and water.

Answer 1

so we add hay single displacement Reaction & A more vreactue melare there Mg) neres super . a Ress reachine metal (H) and the following reaction occur Mg(s) + Hu(e) → MgCl24) + Holg) no. of H and Cl on night is 2 and left side is I a factor of the 2 in front of Hal. Balanced Egn:- AH = - 307.40 kJ Reaction o' - Mg(s) + 2H1 (1) Mg(s) + ahal (1) ▼ Machy + H2(g) br Double asplacement Reaction is on these case two metal exchange their position , - MgO + Hal - Mgel +H2o Add a factor of 2 å front of Hel to balance the equ : Balanced San Reaction @ :- Mgot dhe → MgCl + Ho stas -8-4kJ c. Formation of water from the and O. 242 CG the → 2H30 (8) Reaclion 3 HH3 = -526 mol dy formation of magnesium oxide fom magnesium and origen мэн ч, (1) — ма? add faclor a ů font of Mg as Mgo to obtain a balanced Sant Reaction 4:- 2mg tO2 → 2mgo 1902-1967 Scanned with CamScanner