According to the following reaction, how much energy is evolved during the reaction of 32.5 g b2h6 and 72.5 g cl2? the molar mass of b2h6 is 27.67 g/mol. b2h6(g) + 6 cl2(g) → 2 bcl3(g) + 6 hcl(g) δh°rxn = -1396 kj according to the following reaction, how much energy is evolved during the reaction of 32.5 g b2h6 and 72.5 g cl2? the molar mass of b2h6 is 27.67 g/mol. b2h6(g) + 6 cl2(g) → 2 bcl3(g) + 6 hcl(g) δh°rxn = -1396 kj a) 1640 kj b) 1430 kj c) 429 kj d) 3070 kj e) 238 kj.

The amount of heat evolved during the reaction is 238 kJ

Explanation:

To calculate the number of moles, we use the equation:

    .....(1)

Given mass of = 32.5 g

Molar mass of = 27.67 g/mol

Putting values in equation 1, we get:

Given mass of chlorine gas = 72.5 g

Molar mass of chlorine gas = 71 g/mol

Putting values in equation 1, we get:

For the given chemical equation:

By Stoichiometry of the reaction:

6 moles of chlorine gas reacts with 1 mole of

So, 1.021 moles of chlorine gas will react with = of

As, given amount of is more than the required amount. So, it is considered as an excess reagent.

Thus, chlorine gas is considered as a limiting reagent because it limits the formation of product.

Moles of reacted = 0.170 moles

Amount of heat released for 1 mole of = 1396 kJ

So, amount of heat released for 0.170 moles of

Hence, the amount of heat evolved during the reaction is 238 kJ

c is the answer because when something is left after something evaporates that shows the chemical change.