Answer:
pH of the final solution = 3.8
Explanation:
Concentration of NaF = 
molar
= 0.3 molar
NaF → Na⁺ + F⁻
HF ⇆ H⁺ + F⁻
- NaF is strong electrolyte so completely ionized but HF weak acid not completely ionized.
- Since F⁻ is common ion here
according to common ion effect dissociation of weak acid decreases.
Ka = ![\frac{[H]^{+}[F]^{-} }{[HF]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BH%5D%5E%7B%2B%7D%5BF%5D%5E%7B-%7D%20%20%7D%7B%5BHF%5D%7D)
⇒ [H⁺] = ![\frac{K_{a} [HF]}{[F]^{-} }](https://tex.z-dn.net/?f=%5Cfrac%7BK_%7Ba%7D%20%5BHF%5D%7D%7B%5BF%5D%5E%7B-%7D%20%7D)
...............(1)
{Ka of HF = 3.5 x 10⁻⁴} & Concentration of HF = 30 x 4 x 10⁻³ = 0.12 molar
from equation 1
⇒ [H⁺] = 
[Concentration of F⁻ ≡ Concentration of NaF]
⇒ [H⁺] = 0.00014
⇒pH = - log 0.00014 = 3.85
Weathering is the process of breaking large rocks and boulders into much smaller ones. Weathering can be brought about by wind and water mostly. Sometimes even biological forces account for some types of weathering.
The factors affect wave height is the duration of the wind
Answer:
<h2>D. Nonpolar molecules</h2>
Explanation:
The non-polar molecules are held in place by very weak van der Waals forces, hence making it to have the least melting and boiling point.
The melting points of substances is the point at which it changes from solid to liquid, it can be very difficult to ascertain that why mostly the melting point is given as a range of values.
According to the law of conservation of matter, the number of Atoms<span> is not changed by a chemical reaction.
</span><span>
They're the same before and after a chemical reaction</span>
