Question

In the periodic table, which group contains elements that are all gases at room temperature
A.VI A group
B.VII A group
C.VIII A group
D.V A group

Answer 1

To answer this question, you should recall the formation of the periodic table. The modern periodic law developed by Moseley states that the physical and chemical properties of elements are the periodic function of their atomic number. The elements which are light and stable in their elementary form are present as gas in room temperature.

Complete Step by step solution:
The group that contains elements that are all gases at room temperature is the group of noble gases or the VIII A group. The elements of these groups are colourless, odourless, tasteless, and non-flammable gases under standard conditions. As all of them are inert monatomic elements, their boiling points are extremely low.
These gases have a wide range of applications ranging from incandescent lighting to excimer lasers. Xenon is used as an anaesthetic as it is highly soluble in lipids. This property makes it more potent than the usual nitrous oxide. It also finds use inside medical imaging of the lungs through MRI. Radioactive Radon is used in radiotherapy.

Hence, the correct option is C.

Note: There are 4 blocks in the periodic table: s-block, p-block, d-block and f-block. All of the s-block elements are metals. Usually, they are shiny, silvery, good conductors of heat and electricity, and lose their valence electrons easily. The p-block due to their unique electronic configuration has the biggest variety of elements and is the only block that contains three types of elements: metals, nonmetals and metalloids. d-block elements have properties that are between s-block elements and p-block elements properties. It consists of transition metals. The f-block elements are mostly radioactive. The block names were created to represent the quality of the spectroscopic lines of the atomic orbitals.