Kcet

Which of the following is not true? 

(1) Natural rubber has ‘trans’ configuration at every double bond. 

(2) Natural rubber is 1, 4-polymer of isoprene. 

(3) In vulcanisation the rubber becomes harder and stronger. 

(4) Buna-S is a co-polymer of Butene and styrene. 

The edible part of the fruit of apple is 

(1) Endocarp 

(2) Thalamus 

(3) Involucre 

(4) Pericarp

Let * be a binary operation defined on R by a * b = a+b/4 ∀ a, b ∈ R then the operation * is

(1) commutative but not associative 

(2) neither associative nor commutative 

(3) commutative and associative 

(4) associative but not commutative

Which of the following is incorrect in a galvanic cell? 

(1) Reduction occurs at cathode 

(2) The electrode at which electrons are lost is called cathode 

(3) Oxidation occurs at anode 

(4) The electrode at which electrons are gained is called cathode

Match the plant structures given in the column-I with their plants given in the column-TI.

(1) A – q, B – s, C – r, D – p 

(2) A – r, B – p, C – s, D – q 

(3) A – q, B – s, C – p, D – r 

(4) A – s, B – r, C – p, D – q

If cos α, cos β, cos γ  are the direction cosines of a vector a,then cos 2α + cos 2β + cos 2γ  is equal to 

(1) 3 

(2) 0 

(3) 2

(4) -1

The number of isomers possible for the octahedral complex [CoCl₂(en)(NH₃)₂]⁺ is, 

(1) Three 

(2) Four isomers 

(3) Two 

(4) No isomer

HCl gas is covalent and NaCl is an ionic compound. This is because 

(1) Hydrogen is a non-metal 

(2) Electronegativity difference between H and Cl is less than 2.1 

(3) Sodium is highly electro positive 

(4) HCl is a gas

One of the following area is an example for secondary succession, if the succession takes place in/on 

(1) newly created pond 

(2) abandoned farm land 

(3) bare rock 

(4) newly cooled lava

What is the role of competitive inhibitor during enzyme action? 

(1) It alters the active site of the enzyme and prevents the binding of substrate 

(2) It enhances enzyme action 

(3) It inhibits breaking of chemical bonds of the substrate 

(4) It declines the enzyme action