Calculate the volume occupied by 2.00 moles of H2 at 300.0 Kand 1.25
atm

39.4 Liters

Explanation:

Using the general gas law equation as follows:

PV = nRT

Where;

P = pressure (atm)

V = volume (L)

n = number of moles (mol)

R = gas law constant (0.0821 Latm/molK)

T = temperature (K)

According to the information provided in this question;

P = 1.25atm

V = ?

T = 300K

n = 2.00mol

Using PV = nRT

V = nRT/P

V = (2 × 0.0821 × 300) ÷ 1.25

V = 49.26 ÷ 1.25

V = 39.41

V = 39.4 Liters

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.