27. The first five ionization energies of an element, X, are shown in the table. Ionization energy 1st 2nd 3rd 4th 5th Value / kJ mol-1 631 1235 2389 7089 8844 What is the mostly likely formula of the oxide that forms when X burns in oxygen A. X20 O B. XO I C. X203 D. XO2

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2

answerto predict;