The elements of which group are nonreactive?
halogens
alkaline
earth metals
noble gasses
alkali metals

The group of elements that are non-reactive is noble gases. This is because their full shells prevent reactivity.

so here we go

atomic mass

239 + 1 = y + 134 + 3 combine like terms

240 = y + 137             subtract 137 from both terms

240 - 137 = y

103 = y

atomic number

94 = z +54 + 0

94 = z + 54               subtract 54 from both sides.

40 = z

answer

o conteúdo de calor de um sistema é igual à entalpia apenas para um sistema que é constante