Basic Chemistry: Electrons, Protons and Neutrons, Electrons Are Important for Several Reasons

Table of Contents

1. Introduction
2. Atoms and Elements
3. Atomic number and atomic mass
4. Periodic Table and Chemical Bonds
5. Isotopes
6. Radioisotopes
7. Periodic Table and Chemical Bonds
8. Electronegativity
9. Chemical Bond
10. Compound, substance, Molecule
11. Acidity and Basicity
12. Redox Reaction

Learning Outcomes

After studying this lesson, you shall be able to: Electron and Proton

Electrons

1. Electrons are small components which revolve around the nucleus. Electron has a negative charge.
2. An atom with no net electrical charge has the same number of electrons and protons.
3. Electrons are restricted to certain energy levels i.e.. “shells” and orbitals within those energy levels.
4. These energy levels and orbitals fill in a regular pattern from the lowest energy level outward.
5. Here is an illustration of the orbitals of a Helium atom՚s outer energy level.

Helium Atom Electrons, Protons and Neutrons

Electrons Are Important for Several Reasons

1. Chemical bonds are formed when electrons are transferred or shared between atoms.
2. The arrangement of electrons in the atom of an element helps to determine the chemical properties of an element.
3. For example, when the outer most energy level of an atom is almost empty, the atoms of the element tend to give up electrons.

1. A good example is sodium.
2. When the outermost energy level of an atom is almost (but not completely) full, the atoms of the element tend to grab electrons from other atoms.
3. A good example is chlorine.

1. Finally, electrons can carry and store energy and this is important in understanding metabolism.
2. Every time a chemical reaction takes place, electrons are shared or transferred between atoms and hence energy is shared or transferred.
3. For example, in photosynthesis light energy is captured and stored by electrons.
4. Then the electrons are used to make glucose, and other organic molecules which store the energy as potential energy in their chemical bonds.

Protons

1. The proton is a subatomic particle with the symbol p or p + and a positive electric charge of 1 elementary charge.
2. One or more protons are present in the nucleus of each atom, along with neutrons.
3. The number of protons in each atom is its atomic number.

4. The name proton was given to the hydrogen nucleus by Ernest Rutherford in 1920, because in previous years he had discovered that

5. the hydrogen nucleus (known to be the lightest nucleus) could be extracted from the nuclei of nitrogen and was thus a candidate to be a fundamental particle and building block of all complex atomic nuclei.

MCQs

1. How many protons are present in Helium atom?

1. 3

2. 2

3. 1

4. 4

Answer: B. 2

2. Which among the following is a lightest nucleus?

1. Hydrogen nucleus

2. Oxygen nucleus

3. Nitrogen nucleus

4. Helium nucleus

Answer: A. Hydrogen nucleus

#electrons

#protons