B5h9(l) is a colorless liquid that will explode when exposed to oxygen. how much heat is released when 0.211 mol of b5h9 reacts with excess oxygen where the products are b2h3(s) and h2o(l). the standard enthalpy of formation of b5h9(l) is 73.2 kj/mol, the standard enthalpy of formation of b2h3(s) is -1272 kj/mol and that of h2o(l) is -285.4 kj/mol. express your answer in kj.

958 kJ  heat is released when 0.211 mol of reacts with excess oxygen.

Explanation:

The balanced chemical reaction is,

The expression for enthalpy change is,

where,

n = number of moles

(as heat of formation of substances in their standard state is zero

Now put all the given values in this expression, we get

Thus 2 moles of release heat = 9075.9 kJ

0.211 moles of release heat =

"the periodic table is arranged in order of atomic number."

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.