Na₂CO₃(s) → 2Na⁺(aq) + CO₃²⁻(aq)
The sodium carbonate formed from a strong base and a weak acid. Hydrolysis is subjected to the anion of a weak acid.
CO₃²⁻ + H₂O ⇄ HCO₃⁻ + OH⁻
HCO₃⁻ + H₂O ⇄ H₂CO₃ + OH⁻
pH>7 alkaline solution
2Na⁺ + CO₃²⁻ + 2H₂O ⇄ 2Na⁺ + 2OH⁻ + H₂CO₃
Answer:
Cabon-12 has same average atomic weight and mass number.
Explanation:
carbon-12 has average atomic weight 12 amu and mass number of 12.
amu represents average of mass of a nucleon.
As carbon-12 has same average atomic mass and mass number therefore carbon-12 is a good standard to determine average mass of a nucleon.
Again, abundance of carbon-12 isotope is almost equal to 99%. Therefore fluctuation of average atomic weight from 12 amu is very very low.
So, carbon-12 is taken as a standard to determine mass of a nucleon.
Hence atomic mass of carbon-12 is 12 amu.
Answer is: Prepare to measure pH change.
For example for strong acid-base titration, sodium hydoxide and hydrochloric can be used.
Balanced chemical reaction: HCl + NaOH → NaCl + H₂O.
In this reaction pH of equivalence point will be always 7.
Equivalence point is the point which there is stoichiometrically equivalent amounts of acid and base.
Chemist can draw pH curve (graph showing the change in pH of a solution, which is being titrated) for titration and determine equivalence point.
Near equivalence point indicator should change color, so we must pick indicator who change color near pH of equivalence point.
One kilogram is the answer
Complete balanced equation: 2HNO₃ + Ca(OH)₂ → Ca(NO₃)₂ + 2H₂O
Ionized equation (with spectator ions):
2H⁺ + 2NO₃⁻ + Ca²⁺ + 2OH⁻ → Ca²⁺ + 2NO₃⁻ + 2H₂O
By eliminating the ions that are the same of both sides of the equation (spectator ions):
2H⁺ + 2OH⁻ → 2H₂O [Net Ionic Equation]
