What is the pH of a solution when 0.1 M of Na2CO3 is dissolved in water? (2023)
Practice Questions
1 question
Q1
What is the pH of a solution when 0.1 M of Na2CO3 is dissolved in water? (2023)
10.3
11.0
11.5
12.0
Na2CO3 is a salt of a weak acid (H2CO3) and a strong base (NaOH). The pH can be estimated using the hydrolysis of CO3^2- which gives a pH around 11.0.
Questions & Step-by-step Solutions
1 item
Q
Q: What is the pH of a solution when 0.1 M of Na2CO3 is dissolved in water? (2023)
Solution: Na2CO3 is a salt of a weak acid (H2CO3) and a strong base (NaOH). The pH can be estimated using the hydrolysis of CO3^2- which gives a pH around 11.0.
Steps: 5
Step 1: Identify the compound. Na2CO3 is sodium carbonate, which is a salt formed from a weak acid (carbonic acid, H2CO3) and a strong base (sodium hydroxide, NaOH).
Step 2: Understand that when Na2CO3 dissolves in water, it dissociates into Na+ ions and CO3^2- ions.
Step 3: Recognize that CO3^2- (carbonate ion) can react with water in a process called hydrolysis, which can affect the pH of the solution.
Step 4: Write the hydrolysis reaction: CO3^2- + H2O ⇌ HCO3^- + OH-. This reaction produces hydroxide ions (OH-), which increase the pH of the solution.
Step 5: Since Na2CO3 is a salt of a weak acid and a strong base, the solution will be basic. The pH can be estimated to be around 11.0.
