The number of moles in a substance indicates the amount of the substance that contains the same number of particles as 12 g of the Carbon-12 isotope [or equivalent to 6.02 × 10²³] (which is used as a standard in the world of moles).
Now,
if 6.02 × 10²³ atoms are found in 1 mole ofsodium
then let 9.76 × 10¹² atoms are found in x
⇒ x = (9.76 × 10¹² ) ÷ (6.02 × 10²³)
= 1.619 × 10⁻¹¹ mol
Now, mass = moles × molar mass
∴ mass of Na = 1.619 × 10⁻¹¹ mol × 23 g/mol
= 3.72 × 10⁻¹⁰ g
The gas will obey Boyles Law:
P1 V1 = P2 V2 where P1 and V1 are the original pressure and volume and P2 and V2 are the new values.
If V2 = 2V1 (given) then:
P1 V1 = P2 *2 V1
P2 = P1 V1 / 2V1
P2 = P1 / 2
In other words the pressure is halved. (answer).
D. More collisions occur and the time required for the reaction decreases
This happens because according to collision theory, when energy (in this case, thermal energy) is applied to particles, they move/vibrate more quickly.
