Given these reactions, where X represents a generic metal or metalloid 1) H2(g)+1/2 O2(g)⟶H2O(g)Δ1= −241.8 kJ

2) X(s)+2Cl2(g)⟶XCl4(s)Δ2= +139.7 kJ

3) 1/2H2(g)+1/2Cl2(g)⟶HCl(g)Δ3= −92.3 kJ

4) X(s)+O2(g)⟶XO2(s)Δ4= −531.1 kJ

5) H2O(g)⟶H2O(l)Δ5= −44.0 kJ

what is the enthalpy, Δ,
for this reaction?

XCl4(s)+2H2O(l)⟶XO2(s)+4HCl(g)

For a research project, a student decided to test the effect of the lead(ii) ion (pb2+) on the ability of salmon eggs to hatch. this ion was obtainable from the water‐soluble salt, lead(ii) nitrate, which the student decided to make by the following reaction. pbo(s) + 2 hno3(aq) → pb(no3)2(aq) + h2o losses of product for various reasons were expected, and a yield of 86.0% was expected. in order to have 5.00 g of product at this yield, how many grams of pbo should be reacted? (assume that sufficient nitric acid, hno3, would be used.)