The ratio of radioactive and non radioactive form of an element in sample of rock is 1:7.Estimate the age of rock if the half life of radioactive element is 3.1 billion years. 1-3.1billion years, 2-9.3billion years
It is possible to determine the age of rocks by the method of radioactive dating.
Given:
The half life (t ½) of the radioactive element = 3.1 billion years.
This means that if we begin with a pure sample of the element, we know that in 3.1 billion years, half of the element will have decayed to another isotope.
Now, the ratio of radioactive and non-radioactive element = 1:7
This means that subsequent decays have reduced the radioactive element to non-radioactive element and now, the ratio is 1:7
After 1 half life (3.1 billion years) =1/2 remains
After 2 half lives (6.2 billion years) = 1/4 remains
After 3 half lives (9.3 billion years) = 1/8 remains
The given ratio is 1: 7.
So, approximately after 3 half lives, the age of the rock would be 9.3 billion years.
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
You have rated this answer /10
Browse free questions and answers by Chapters
- 1 Biomolecules
- 2 Cell : The Unit of Life
- 3 Respiration in Plants
- 4 Animal Kingdom
- 5 Evolution
- 6 Ecosystem
- 7 The Living World
- 8 Biological Classification
- 9 Reproduction in Organisms
- 10 Sexual Reproduction in Flowering Plants
- 11 Human Reproduction
- 12 Reproductive Health
- 13 Principles of Inheritance and Variation
- 14 Molecular Basis of Inheritance
- 15 Biotechnology : Principles and Processes
- 16 Biotechnology and its Applications
- 17 Human Health and Disease
- 18 Microbes in Human Welfare
- 19 Strategies for Enhancement in Food Production
- 20 Organisms and Populations
- 21 Biodiversity and Conservation
- 22 Environmental Issues
- 23 Plant Kingdom
- 24 Morphology of Flowering Plants
- 25 Anatomy of Flowering Plants
- 26 Structural Organisation in Animals
- 27 Cell Cycle and Cell Division
- 28 Mineral Nutrition
- 29 Photosynthesis in Higher Plants
- 30 Plant Growth and Development
- 31 Digestion and Absorption
- 32 Breathing and Exchange of Gases
- 33 Body Fluids and Circulation
- 34 Excretory Products and their Elimination
- 35 Locomotion and Movement
- 36 Neural Control and Coordination
- 37 Chemical Coordination and Integration
- 38 Transport in Plants
