Question

1.Which of the following is not true of polar covalent bonds?

Answer 1

Answer: For question 1, correct option is D.

For question 2, correct option is B.

Explanation:

For question 1: A polar covalent bond is the chemical bond where electrons are unequally shared between the two different elements having different electrongativities. 2 poles are generated in this bond.

According to Pauling's electronegativity rule, difference between the electronegativities of elements in a polar covalent bond is from 0.5 to 2.0

Hence, polar covalent bond can never exist between the atoms of the same element.

For Question 2:

Option 1: Inhibitor decreases the rate of the reaction, but we are removing the inhibitor, so the rate will be increased.

Option 2: For a reaction,

$aA+bB\rightarrow cC+dD$

$rate=k[A]^a[B]^b$

As rate is directly proportional to the reactants, so by lowering the concentration of the reactants, the rate will also decrease.

Option 3: By increasing the temperature, collisions also increases and this collision results in the formation of the product. Hence, increasing the rate of the reaction.

Option 4: Adding a catalyst increases the rate of the reaction by lowering down the activation energy of the reactants.