Question

Write the atomic number, atomic mass, number of protons, electrons and neutrons for the first 5 elements.

Answer 1

let no of protons be z electron be y atomic no be x and neutron be r and mass be m

elements z. y. x. r. m

hydrogen 1. 1. 1. 0 1

helium. 2. 2. 2. 2. 4

carbon. 6. 6. 6. 6. 12

nitrogen. 7. 7. 7. 7. 14

Answer 2

Answer:

Atomic information about first five elements.

Explanation:

$\begin{array}{|c|c|c|c|c|}\cline{1-5}\large{\sf\:Elements} & \large{\sf\:Atomic\:No.} & \large{\sf\:Atomic\:Mass} & \large{\sf\:No.\:of\:Protons\:=\:No.\:of\:Electrons} & \large{\sf\:No.\:of\:Neutrons}\\\cline{1-5}\sf\:Hydrogen & \sf\:1 & \sf\:1 & \sf\:1 & \sf\: 0\\\cline{1-5}\sf\:Helium & \sf\:2 & \sf\:4 & \sf\:2 & \sf\:2\\\cline{1-5}\sf\:Lithium & \sf\:3 & \sf\:7 & \sf\:3 & \sf\:4\\\cline{1-5}\sf\:Beryllium & \sf\:4 & \sf\:9 & \sf\:4 & \sf\:5\\\cline{1-5}\sf\:Boron & \sf\:5 & \sf\:11 & \sf\:5 & \sf\:6\\\cline{1-5}\end{array}$

Additional Information:

1. Elements:

The substances in their pure form are known as elements.

2. Symbols of Elements:

There are 115+ elements.

To denote them in a reaction, certain symbols are used.

3. Protons:

The positively charged particles present in an atom of an element are called protons.

4. Electrons:

The negatively charged particles present in an atom of an element are called as electrons.

5. Neutrons:

The particles present in an atom of an element having no charge are called as neutrons.

6. Atomic number:

The number of protons present in an atom of an is called atomic number.

Atomic number is equal to number of electrons before any chemical reaction.

It is denoted by 'Z'.

7. Atomic mass:

The sum of number of protons and neutrons present in an atom of an element is called atomic mass.

It is denoted by 'A'.