-Positively charged nucleus
-Empty spaced
-Dense core
Answer:
Ksp = 2.74 x 10⁻⁵
Explanation:
The solubility equilibrium for Ca(OH)₂ is the following:
Ca(OH)₂(s) ⇄ Ca²⁺(aq) + 2 OH⁻(aq)
I 0 0
C + s + 2s
E s 2s
According to the ICE table, the expression for the solubility product constant (Kps) is:
Ksp = [Ca²⁺] x ([OH⁻])² = s x (2s)² = 4s³
Then, we calculate Ksp from the solubility value (s):
s = 0.019 M
⇒ Ksp = 4s³ = 4 x (0.019)³ = 2.74 x 10⁻⁵
As we know that one mole of any Ideal gas at standard temperature and pressure occupies exactly 22.4 dm³ volume.
Solution for problem:
When 1 mole Neon (Ne) occupies 22.4 dm³ at STP then the volume occupied by 2.25 moles of Neon is calculated as,
= ( 22.4 dm³ × 2.25 moles ) ÷ 1 mole
= 50.4 dm³ 1dm³ = 1 L
Result:
So, 50.4 dm³ (Liter) volume will be occupied by 2.25 moles of Neon gas if it acts ideally at STP.

The Correct pair of Element and it's symbol ~