Isotopes And Electronic Structure Of An Atom

CHAPTER 2 : THE STURUCTURE OF THE ATOM

2.3 Isotopes & Their Importance 2.4 The Electronic Structure of an Atom

2.3 Isotopes & Their Importance

At the end of this lesson, you should be able to:

1. 2. 3. 4.

State the meaning of isotopes. List 3 examples of elements with isotopes. Determine the number of subatomic particles of isotopes. Justify the uses of isotopes in daily life.

ISOTOPES Atoms of the same element with different number of neutrons

How about the Nucleon No. & Proton No.???

ISOTOPES Atoms of the same element with different number of neutrons

Isotopes have the SAME PROTON NO. but DIFFERENT NUCLEON NO. Isotopes of Hydrogen:

Some examples of isotopes of elements:

Give another example of isotopes of an element

Cobalt-60 Used in radiotherapy for the treatment of cancer

Sodium-24 Used to detect leaks in pipes carrying gas Carbon-14

Uses of Isotopes

Phosphorus-32 Used in fertilizers to study the metabolism of phosphorus in plant

Used in carbon dating to estimate the age of fossils & artifacts Oxigen-18 Is a biological tracer used in the studies of photosynthesis in plant

GROUP ASSIGNMENT Describe the usage of isotopes in various fields: 1. Medicine 2. Industry 3. Agriculture 4. Archeology Please state your references…

2.4 The Electronic Structure of an Atom

At the end of this lesson, you should be able to:

1.

2. 3. 4.

Describe the electron arrangements of atoms of elements with the proton numbers of 1 to 20. Draw electron arrangement of an atom in an element. State the meaning of valence electrons. Determine the number of valence electrons from the electron arrangement of an atom.

ELECTRONIC CONFIGURATION The arrangement of electrons around the nucleus in the shells of an atom 1st shell : max. 2e 2nd shell : max. 8e 3rd shell : max. 8e Electrons Nucleus Valence electrons : e in outermost shell

Electronic Configuration of some Elements

What have you learnt today? • Meaning of ISOTOPES • Meaning of ELECTRONIC CONFIGURATION • Maximum number of electrons in the 1st shell, 2nd shell and 3rd shell • Meaning of VALENCE ELECTRONS