A gas sample occupies a volume of 140 mL at a temperature of 296 K and a pressure of 98.2kPa. how many moles of gas are there? show work.

0.00559 mol

Explanation:

The following data were obtained from the question:

V = 140mL = 0.14L

T = 296K

P = 98.2kPa = 98200Pa

Recall: 101325Pa = 1atm

98200Pa = 98200/101325 = 0.97atm

R = 0.082atm.L/Kmol

n =?

The number of mole (n) can be obtained as follows:

PV = nRT

n = PV /RT

n = (0.97x0.14)/(0.082x296)

n = 0.00559 mol

Therefore, the number of mole of the gas present is 0.00559 mol

answer: enthalpy

explanation:

for a exothermic reaction, the energy is released i.e. the energy of the products is lower than the energy of the reactants.

= enthaply

= energy of products

= energy of reactants

as , thus comes out to be negative. negative value of enthalpy shows that the reaction is exothermic.