Potassium phenolate is obtained by reaction. 4.7 g of phenol and 120 g of potassium hydroxide solution with
Potassium phenolate is obtained by reaction. 4.7 g of phenol and 120 g of potassium hydroxide solution with a mass fraction of KOH equal to 14%. What is the mass of finolate?
Given:
m (C6H5OH) = 4.7 g
m solution (KOH) = 120 g
ω (KOH) = 14%
Find:
m (phenolate) -?
Solution:
1) Write the reaction equation:
C6H5OH + KOH => C6H5OK + H2O;
2) Calculate the amount of phenol substance:
n (C6H5OH) = m (C6H5OH) / M (C6H5OH) = 4.7 / 94 = 0.05 mol;
3) Calculate the mass of alkali:
m (KOH) = ω (KOH) * m solution (KOH) / 100% = 14% * 120/100% = 16.8 g;
4) Calculate the amount of alkali substance:
n (KOH) = m (KOH) / M (KOH) = 16.8 / 56 = 0.3 mol;
5) Determine the amount of phenolate substance:
n (C6H5OK) = n (C6H5OH) = 0.05 mol;
6) Calculate the mass of phenolate:
m (C6H5OK) = n (C6H5OK) * M (C6H5OK) = 0.05 * 132 = 6.6 g.
Answer: The mass of C6H5OK is 6.6 g.