The homologous structures and the analogous structures of different species.
Halogens are noble gasses, located on the far left of the periodic table. They are used partly for lighting, and are of great importance to scientists because they don't "mingle" easily with other elements.
Answer:
3.62x10⁻⁷ = Kb
Explanation:
The acid equilibrium of a weak acid, HX, is:
HX + H₂O ⇄ X⁻ + H₃O⁺
Where Ka = [X⁻] [H₃O⁺] / [HX]
And basic equilibrium of the conjugate base, is:
X⁻ + H₂O ⇄ OH⁻ + HX
Where Kb = [OH⁻] [HX] / [X⁻]
To convert Ka to Kb we must use water equilibrium:
2H₂O ⇄ H₃O⁺ + OH⁻
Where Kw = 1x10⁻¹⁴ = [OH⁻] [H₃O⁺]
Thus, we can obtain:
Kw = Ka*Kb
Solving for Kb:
Kw / Ka = Kb
1x10⁻¹⁴ / 2.76x10⁻⁸ =
3.62x10⁻⁷ = Kb
A mole of sodium chloride has mass 58.44 grams. You get that from adding the molar masses of sodium and chlorine, which are listed on the periodic table.
<span>58.44 g/mol * 4.40 mol = 257.1 or ≈ 257 grams with 3 significant figures</span>