Consider the reaction for the formation of aluminum oxide from aluminum and oxygen. 4Al(s)+3O2(g)⟶2Al2O3(s) ΔH1 Express the enthalpy of the following reaction, ΔH2, in terms of ΔH1. 2Al2O3(s)⟶4Al(s)+3O2(g) ΔH2 ΔH2= Express the enthalpy of the following reaction, ΔH3, in terms of ΔH1. 12Al(s)+9O2(g)⟶6Al2O3(s) ΔH3 ΔH3= Express the enthalpy of the following reaction, ΔH4, in terms of ΔH1 2Al(s)+3/2O2(g)⟶Al2O3(s)ΔH4 ΔH4=

a electronegativity decreases beacuse the size of nucleus is bigger.

yes

ya te ayud espera

a. the law of proportion states the combination of 2 atoms in a specific ratio to produce multiple compounds such as the given statement of question ‘1st compound contains 88.8 % cu ’ indicates 88.8 g of cu is present along with 11.2 g oxygen in 100 g of compound whereas the statement ‘2st compound contains 79.9 % cu ’ indicates 79.9 g of cu is present along with 20.1 g oxygen in 100 g of compound

1st compound contains 88.8 g cu

for cu

m = 63 g /mol

atomic % = 88.8 /63 = 1.42

for o

m = 16 g /mol

atomic % = 11.2 /16 = 0.7

b. the emperical formula of 1st compound is

cu1.4o0.7

cu2o