NEET Test 74

Metallic or non-stoichiometric hydrides can only be formed by d-block and f-block elements like Pt, Pd, La, Y etc. The rest of the elements form either ionic or molecular hydride. Non-Stoichiometric hydrides are hydrogen-deficient compounds formed by the reaction of dihydrogen with d-block and f-block elements. These hydrides do not follow the law of constant composition.

Hence, the correct option is (C).

To test for chlorine, use damp blue litmus paper. The blue colour will turn red and then to white. Chlorine gas reacts with water to produce an acidic solution which is also an effective bleach. This explains how the test for chlorine works. The acidic solution formed on the damp litmus paper turns the indicator red. Then the bleach turns the red colour to white.

Hence, the correct option is (B).

In Pistia (water lettuce) vegetative propagation occurs by offset where one intemode long runners grows horizontally along the soil surface and gives rise to new plants either from axillary or terminal buds.

Hence, the correct option is (A).

The increasing order of the reactivity of the halides for the S_N1 reaction is (II)<(I)<(III).

(II) is primary alkyl halide.

(I) is secondary alkyl halide.

Primary alkyl halide is less reactive towards S_N1 reaction than secondary alkyl halide.

In (III), the carbocation generated is stabilised due to resonance. Hence, (III) is most reactive towards S_N1 reaction.

Hence, the correct option is (A).

Photorespiration is a process in plant metabolism where the enzyme RuBisCO oxygenates RuBP instead of getting carboxylated. This process reduces the efficiency of photosynthesis by 25% in C₃ plants. In it, plants use oxygen and release carbon dioxide as by product that making use of it. Photorespiration is generally found to occur in peroxisome.

It more in common in C₃ plants as they have higher CO₂ compensation point due no net evolution of carbon dioxide gas because the rate of photosynthesis (which consumes carbon dioxide) is equal to the rate of respiration (which evolves carbon dioxide).

In a normal photosynthesis process, there is light reaction and dark reaction. In the light reaction, photophosphorylation occurs to generate ATP which will be utilised in making of glucose. The photophosphorylation process occurs in both cyclic and non-cyclic steps with the involved of the photosystem I and II. Dark reaction or light independent reaction process reduces carbondioxide to glucose using the enzyme RuBisCO.

Hence, the correct option is (A).