Vybbybybtbyyybybybybybbynununununynynynynynynynynynynynynynynynynynynunynynynynyninununununununnunubynununununununu
Hess law can help us to obtain the enthalpy of a series of reactions by summation. The missing enthalpy of this reaction is −198kJ.
<h3>
What is Hess law?</h3>
According to the Hess law of constant heat summation, the enthalpy of a sequence of reactions can be obtained as the sum of the enthalpies of all the reactions.
Now looking at all the reavtion written here in order to obtain the missing enthalpy, we conclude that the missing enthalpy is −198kJ.
Learn more about enthalpy: brainly.com/question/3393755
The mass percent of oxygen is 32.82%.
<h3>What is a noble gas?</h3>
A noble gas is member of group 18 in the periodic table. The members of this group are known not to be reactive and they do not easily form compounds. However, there have been few compounds of the members of group 18 that have been reported.
Let us now calculate the relative molecular mass of xenon tetraoxide.
Xe + 4 (O)
131 + 4(16) = 195
Given that the mass of oxygen in the compound is 64, the mass percent of oxygen in xenon tetroxide is obtained from;
64/195 * 100/1
= 32.82%
Learn more about mass percent:brainly.com/question/5394922
#SPJ1
214.0560
+ 9.3456
=223.4016
