Question

Match the atomic number 2,4,8,15, and 19 with each of the following-
An element belonging to group 2.

Answer 1

Hint: Group 2 comprises light, silver metals with less metallic quality than Group 1 elements. While certain features are similar in the group, heavier metals such as Ca, Sr, Ba and Ra are just as reactive as Group 1 Alkali metals.
Both the elements in Group 2 have two electrons in their valence shells, granting them a +2-oxidation status. This makes it easy for the metals to lose electrons, which increases their stability and allows them to form compounds through ion bonds.

Step-By-Step answer:
Beryllium (Be) is an element of Group 2 (alkaline earth metals). It has a nuclear number of 4.
Phosphorus with symbol P is a solid non-metal belonging to the third period with atomic number 15.
Potassium metal having symbol (K) has valency 1. The atomic number is 19 so it's an alkali metal.
Helium is a gaseous element with a valency of 2. The symbol with which it is represented is He, and the atomic number is 2. It's an acidic gas. It is a natural gas or neutral gas.
Beryllium is the very first element in Group 2 and has the highest melting point (1560 K) of any of the elements in the group. It is extremely uncommon on Earth as well as in the world, so it is not considered essential for plant or animal existence. It can only be found in compounds with other elements in nature. In solutions, only pH values below 5.5 remain in elementary form. Beryllium is considered to be extremely light with high ionization energy and is used primarily to strengthen alloys.

Note: Helium is a chemical element with the He symbol and the atomic number 2. It is considered as a colourless, odourless, tasteless, non-toxic, inert, monatomic gas which is the first in the noble gas group in the periodic table. Its boiling point is calculated to be the lowest of all the elements.