A solid compound 'X' on heating gives CO2 gas and a residue. The residue mixed with water forms 'Y'. On passing an excess of CO2 through 'Y' in water, a clear solution, 'Z' is obtained. On boiling 'Z', compound 'X' is reformed. The compound 'X' is:
Correct answer: D. CaCO3
- A. Na2CO3
- B. K2CO3
- C. Ca(HCO3)2
- D. CaCO3
Explanation
Upon heating, compound 'X' decomposes into CaO and CO2. The residue from this reaction, when mixed with water, forms Ca(OH)2 (Y). Upon passing an excess of CO2 through Ca(OH)2, it forms CaCO3 and H2O, which upon boiling results in the reformation of compound 'X' (CaCO3). The incorrect options fail to match the observed reactions and compounds formed as described in the question.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About s-Block and p-Block Elements
The s and p blocks are studied through their valence-shell configurations, periodic trends and characteristic chemical properties. Work covers the reactions of Group I and Group II elements, the behaviour of Group IV elements, and how atomic size, ionization energy, electronegativity and metallic character change across periods and down groups.
Practise s-Block and p-Block Elements
1,359 free s-Block and p-Block Elements MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Chemistry questions like this
Chemistry is on 14 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More s-Block and p-Block Elements questions
Be and Al exhibit many properties which are similar. But the two elements differ in:
When washing soda is heated :
A salt 'X' on heating liberates one coloured gas and another colourless gas. Both the gases are paramagnetic. The salt 'X' may be:
Which one of the following characteristics of lithium does not resemble with other alkali metals?
Which of the following ions has largest heat of hydration?
One mole of magnesium nitride on the reaction with an excess of water gives: