How many moles of neon (Ne) gas have a volume of 2.2 L and a pressure of 0.83 atm at 283 K?
(The universal gas constant is 0.0821 L. atm/mol. K.)
O A. 13 mol
O B. 0.11 mol
O C. 42 mol
O D. 0.079 mol

D. 0.079 mol

Explanation:

This question involving the number of moles of neon (Ne) gas can be solved using the ideal gas law, also called the general gas equation.

The formula for the general gas equation is:

PV = nRT

Where;

P=pressure (atm)

V=volume (Litres)

n=amount of substance (mol)

R=ideal gas constant

T=temperature (K)

In this question, P is given as 0.83atm, V = 2.2L, R = 0.0821 L.atm/mol.K, T= 283K, n = ?

We calculate 'n' by making it the subject of the formula i.e.

PV= nRT

Divide both sides by RT, we have;

n = PV/RT

Hence, we input our values

n = 0.83 × 2.2 / 0.0821 × 283

n= 1.826 / 23.2343

n = 0.07859

Hence, n is approximately 0.079 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.