Question

Assertion: Boron is a metalloid.
Reason: Boron shows metallic nature.
(A) Both assertion and reason are true and the reason is a correct explanation of the assertion.
(B) Both assertion and reason are true but reason is not the correct explanation of the assertion.
(C) Assertion is true but reason is false.
(D) Both assertion and reason are false.

Answer 1

In the above question, some assertion about boron as a metalloid is given. We are provided with the information about the metallic nature of boron. We have to check which of the following options suits the best. Since, metalloids are the elements having properties of both metal and non-metal. So, if the assertion is correct then the reason is false or vice-versa.

Complete answer:
A metalloid is a type of chemical element which has properties that are a mixture of those of metals and non-metals. There is no standard definition of a metalloid and non compete agreement on which elements are metalloids.
There are eleven metalloids out of which six are commonly recognised metalloids, they are boron, silicon, germanium, arsenic, antimony, and tellurium. Rest five elements are less frequently used, they are carbon, aluminium, selenium, polonium and astatine. On a standard periodic table, all eleven elements are in a diagonal region of the p-block starting from boron at the upper left to astatine at lower right. Some periodic tables include a region which distinguishes between metals and nonmetals, here metalloids are usually found. Since, boron is one among the eleven metalloid and hence, assertion is true.
Metalloids have physical properties of metals and chemical properties of non-metal. It is a good conductor of electricity as well as it forms alloys with metals. Hence, reason is false as it states that Boron shows metallic nature.
So, we can conclude that the assertion is true but the reason is false.
Hence, option C is the correct option.

Note:
-Boron is used as an insecticide as well as a pesticide.
-Boron trifluoride and trichloride are used as catalysts in organic synthesis.