Answer:
NaOH is limiting
Explanation:
Hcl + NaOH ------------ Nacl + H2O
Given 7.81g 5.24g
mol weights 1+35.5 23+16+1
36.5 40
No of Moles 7.81/36.5 5.24/40
0.2139 0.131
No of moles = weight/ molecular weight
No of moles of NaOH is lower so it is limiting as according to equation one mole of Hcl requires mole of NaOH so equal number of moles are required. NaOH is 0.131 which is far lower than 0.2139
-------- represents arrow in forward direction in equation
Rub the magnet on the iron an it will cause a stronger force of attraction. Hope this helped!
<span>Answer
is: Ka for propinoic acid is 6,57·10</span>⁻⁵.<span>
Chemical reaction: C</span>₂H₅COOH(aq)
+ H₂O(l) ⇄ C₂H₅COO⁻(aq)
+ H₃O⁺(aq).<span>
n(C</span>₂H₅COOH) = 0,04 mol.<span>
V(C</span>₂H₅COOH) = 750 mL = 0,75 L.<span>
c(C</span>₂H₅COOH) = 0,04 mol ÷ 0,75 L.<span>
c(C</span>₂H₅COOH) = 0,053 mol/L = 0,053 M.<span>
[C</span>₂H₅COO⁻]
= [H₃O⁺] = 1,84·10⁻³ M = 0,00184 M.<span>
[HCN] = 0,053 M - 0,00184 M = 0,0515 M.
Ka = [C</span>₂H₅COO⁻] · [H₃O⁺] /
[C₂H₅COOH].<span>
Ka = (0,00184 M)² / 0,0515 M.
Ka = 6,57·10</span>⁻⁵.
