The better era tbh.......
1) Reaction
<span>NH4Cl(s) ---> NH3(g) + HCl(g)
2) equilibrium equation, Kc
Kc = [NH3] * [HCl]
3) Table of equilibrium formation
step concentrations
</span>
<span> NH4Cl(s) NH3(g) HCl(g)
start 1.000 mole 0 0
react - x
produce +x + x
------------------ ---------- -----------
end 1 - x +x +x
1 - x = 0.3 => x = 1 - 0.3 = 0.7
[NH3] = [HCl] = 0.7/0.5 liter = 1.4 (I used 0.500 dm^3 = 0.5 liter)
4) Equilibrium equation:
Kc = [NH3] [HCl] = (1.4)^2 = 1.96
Which is the number that you were looking for.
Answer: Kc = 1.96
</span>
The reaction between the reactants would be:
CH₃NH₂ + HCl ↔ CH₃NH₃⁺ + Cl⁻
Let the conjugate acid undergo hydrolysis. Then, apply the ICE approach.
CH₃NH₃⁺ + H₂O → H₃O⁺ + CH₃NH₂
I 0.11 0 0
C -x +x +x
E 0.11 - x x x
Ka = [H₃O⁺][CH₃NH₂]/[CH₃NH₃⁺]
Since the given information is Kb, let's find Ka in terms of Kb.
Ka = Kw/Kb, where Kw = 10⁻¹⁴
So,
Ka = 10⁻¹⁴/5×10⁻⁴ = 2×10⁻¹¹ = [H₃O⁺][CH₃NH₂]/[CH₃NH₃⁺]
2×10⁻¹¹ = [x][x]/[0.11-x]
Solving for x,
x = 1.483×10⁻⁶ = [H₃O⁺]
Since pH = -log[H₃O⁺],
pH = -log(1.483×10⁻⁶)
<em>pH = 5.83</em>
Answer:
In chemistry, a symbol is an abbreviation for a chemical element. Symbols for chemical elements normally consist of one or two letters from the Latin alphabet and are written with the first letter capitalised.
Earlier symbols for chemical elements stem from classical Latin and Greek vocabulary. For some elements, this is because the material was known in ancient times, while for others, the name is a more recent invention. For example, Pb is the symbol for lead (plumbum in Latin); Hg is the symbol for mercury (hydrargyrum in Greek); and He is the symbol for helium (a new Latin name) because helium was not known in ancient Roman times. Some symbols come from other sources, like W for tungsten (Wolfram in German) which was not known in Roman times.
Explanation: