Kb = [HA} [OH-] / [A-] where [A-] represents the concentration of CN- (.068M)
Kb = Kw / Ka = 1 x10-14 / 4.9 x 10-10 = 2 x 10-5
Since this is a salt solution which could be considered to have formed from the neutralization of a strong base (NaOH) and a weak acid (HCN), the Na+ will have no effect on the pH of the solution while the CN- ion will undergo hydrolysis:
CN- + H2O --> HCN + OH-
Based on this equation, the quantities of HCN and OH- produced must be the same and therefore [HCN]=[OH-]. We will set this equal to x.
Plugging into the original equation yields:
2 x 10-5 = x2 / .068 M
Solving for x yields 1.2 x 10-3 whidh is equal to the [OH-]
The pOH then is equal to -log (1.2x10-3) = 2.9
The pH of the solution would be 14 - 2.9 = 11.1
Answer:
Explanation:
2Al₂O₃ ⟶ 4Al +3O₂
n/mol: 1.26
The molar ratio is 4 mol Al:2 mol Al₂O₃.
Answer:
C2H2
Explanation:
Mass of Carbon in CO2
grams 
gram
Mass of hydrogen in H2O 
grams 
gram
We will calculate the % of C and H in the sample
% C 
%
% H 
%
Number of mole of C 
Number of mole of H 
Fractional share of C 
Fractional share of H 
Empirical Formula = CH
Empirical Mass 
Molecular mass 
Molecular Formula – CHn
N 
Molecular Formula = C2H2
Answer:
Anything that has less density than water will float on water.
Explanation:
Come on! It's basic knowledge!
