Download presentation

Presentation is loading. Please wait.

Published byMaci Knipe Modified over 4 years ago

1
ABSOLUTE AGE Absolute dating- used to determine the age of a rock or fossil more exactly based on the properties of atoms An atom:

2
**In an atom, protons ( + ) and neutrons (neutral)**

are found in the nucleus. Electrons ( - ) are found in orbitals around the nucleus. Every element has an exact number of protons, neutrons and electrons in order to be stable.

3
**An isotope is the same element with a different**

number of neutrons. Atomic mass - number of protons and neutrons combined Radioactive decay - the number of protons in an atom is changed; forms a new element Ex. - If parent material is Uranium (atomic mass 238), And the daughter material is lead ( atomic mass 206); caused by a loss of 32 protons after a long series of decay (Lead is not radioactive and will not decay any further.)

4
**Each radioactive parent material has a certain rate at which it**

decays to its daughter material. Half-life -the time it takes for half of the atoms of the isotope to decay. Ex.- half -life of Carbon 14 is 5730 years, so it will take 5730 years for half of the C-14 in an object to become nitrogen-14

5
**The Half-life of Bismuth**

6
**How can knowing the half-life of Carbon-14 help scientists**

find out the age of a fossil? Radiometric dating - measure amounts of parent/daughter materials; if know half-life of material and original amount, Can calculate absolute age Carbon-14 is useful for dating rocks and fossils up to 75,000 years old. Uranium 238 is used for older objects. Based on radiometric dating, the age of the earth is estimated to be 4.6 billion years.

7
**Try this example problem:**

An object is found to contain 2 grams of C-14. A similar bone (from today) is found to contain 4 g of C-14. Approximately how old is the bone?

Similar presentations

OK

Earth and Space…7b and c (7) Earth in space and time. The student knows that scientific dating methods of fossils and rock sequences are used to construct.

Earth and Space…7b and c (7) Earth in space and time. The student knows that scientific dating methods of fossils and rock sequences are used to construct.

© 2018 SlidePlayer.com Inc.

All rights reserved.

To ensure the functioning of the site, we use **cookies**. We share information about your activities on the site with our partners and Google partners: social networks and companies engaged in advertising and web analytics. For more information, see the Privacy Policy and Google Privacy & Terms.
Your consent to our cookies if you continue to use this website.

Ads by Google

Ppt on metallic and nonmetallic minerals Ppt on different types of plants Ppt on structures in civil engineering Ppt on rutherford's gold foil experiment Ppt on grid connected pv system Ppt on 21st century skills for teachers Ppt on programmable logic controller Ppt on buildings paintings and books Ppt on network security in ieee format Ppt on ms word window with label