IB myp 4-5 Chemistry – Practice Questions- All Topics
Topic :Types of chemical reaction-Acids/Base reactions
Topic :Types of chemical reaction-Weightage : 21 %
All Questions for Topic :acids and bases,neutral solutions,acid/base reactions,$\mathrm{pH}$ and indicators,formation of salts,uses of salts,redox reactions,reactivity series,extraction of metals and corrosion,electrochemical cells
Question:
Write the balanced chemical equation for the reaction between calcium carbonate and hydrochloric acid. Can you predict the gas produced from the composition of the reactants?
▶️Answer/Explanation
Ans: CaCO3(s) + 2HCl(aq) → CaCl2(aq) + CO2(g) + H2O(l)
The carbonate ion CO32– can be seen to contain the gas carbon dioxide CO2 within the formula.
Question:
Describe what you saw happening to the calcium hydroxide solution.
▶️Answer/Explanation
Ans: The colorless calcium hydroxide solution slowly began to turn a milky white colour as the gas carbon dioxide is bubbled through the solution.
Question:
Write a balanced chemical equation for the reaction between calcium hydroxide solution and carbon dioxide gas.
▶️Answer/Explanation
Ans: Ca(OH)2(aq) + CO2(g) → CaCO3(s) + H2O(l)
Question:
Can you deduce how many times greater the concentration of hydrogen ions is in the more acidic of the two solutions?
▶️Answer/Explanation
Ans: For each change in 1 pH unit there is a 10–fold change in the concentration of hydrogen ions. For a difference of 4 pH units, gastric juice has 104 or 10000 times more hydrogen ions than black coffee.