Q2.Why does the solubility of alkaline earth metal carbonates and sulphates in water decrease down the group?
Answer : Option CExplaination / Solution:
Solubility of sulphates and carbonates decreases down the group because of decrease in hydration energy. which is insufficient to over come the lattice energy of ions.
Q4.Heating a pulverised mixture of limestone and clay in a rotary kiln is used in the manufacture of:
Answer : Option DExplaination / Solution:
Heating a pulverised mixture of limestone and clay in a rotary kiln is used in the manufacture of Portland cement
Q7.Alkali metals react with water vigorously to form hydroxides and dihydrogen.Which of the following alkali metals reacts with water least vigorously?
Answer : Option CExplaination / Solution: Li reacts with water least vigorously, since the density of Li is only about half that of water,so it floats on the surface and ultimately dissappears,giving off H2 gas
Q8.The reducing power of a metal depends on various factors. Suggest the factor which makes Li, the strongest reducing agent in aqueous solution.
Answer : Option AExplaination / Solution:
High hydration energy of Li makes it’s a very good reducing agent. Its hydration energy compensates the high ionization energy.
Q9.Metal carbonates decompose on heating to give metal oxide and carbondioxide. Which of the metal carbonates is most stable thermally?
Answer : Option DExplaination / Solution: BaCO3is very stable due to size compatibility factor . A larger cation can stablise a larger anion.Group 2 element become more thermally stable down the group.
Answer : Option AExplaination / Solution: 1st element of 1st group and the second element of 2nd group exist in diagonal relationship.Due to their nearly same polarizing power
Total Question/Mark :
Scored Mark :
Mark for Correct Answer : 1
Mark for Wrong Answer : -0.5
Mark for Left Answer : 0