Free Blocks of the Periodic Table MCQs with Answers

1. The block of the periodic table to which an element belongs is decided by

• A. the number of shells it has
• B. its atomic mass
• C. the subshell that receives the last electron added
• D. whether it is a metal or a non metal

Explanation: Elements are assigned to the s, p, d or f block according to the subshell into which the differentiating electron enters, so groups I and II form the s block and groups III to VIII the p block. This classification explains why elements in the same block share broad chemical behaviour. Period number, by contrast, is given by the number of the outermost shell.

2. An element with the electronic configuration 1s2 2s2 2p6 3s2 3p4 belongs to

• A. group VI of the p block, period 3
• B. group IV of the p block, period 3
• C. group II of the s block, period 3
• D. group VI of the d block, period 4

Explanation: The outermost shell is the third, giving period 3, and it contains six electrons in total across 3s and 3p, giving group VI, while the last electron entered a p subshell so the element is in the p block. The element is sulphur. Counting only the p electrons and answering group IV is the standard error.