Answer:
After 6000 years, approximately 500 atoms of carbon-14 will be left in the femur bone of an animal which had 1000 atoms of carbon-14 when the animal died.
Explanation:
The half-life of a radioactive isotope of an element is the time taken for half the atoms present in a given amount of the element to undergo decay or disintegration. For example, the half-life of carbon-14 isotope is 5730 years. This means that, if there are 100 atoms of carbon-14 present in a given sample of a material, in the next 5730 years, approximately, 50 atoms of carbon-14 will be left in the material.
Since the half-life of radioactive isotopes are constant, these radioactive isotopes are used in the determining the ages of ancient life-forms as well as rocks.
In the given example, after 6000 years, approximately 500 atoms of carbon-14 will be left in the femur bone of an animal which had 1000 atoms of carbon-14 when the animal died.
1. The carbon-dioxide increases in atmosphere by fossil-fuels, decaying-dead, automobiles etc. and when animals or plant die they get buried and carbon content increases under the ground.
2. Greenhouse gas are those gases which trap heat in the atmosphere and maintain the temperature of the earth.
3. Diamond and graphite are solid forms of carbon.
4. Dry ice is the carbon as liquid.
5. Autotrophs make simple sugar glucose via photosynthesis and this sugar is used by heterotrophs as a substrate for respiration in the presence of oxygen.
Explanation:
When the fuels from automobiles, fossil-fuel, dead decaying organism release carbon in the atmosphere, the increase in carbon dioxide is the cause of global warming.
Greenhouse gases absorb the infrared radiations from the earth's surface and reradiate it back to the atmosphere. In short greenhouse gases allow sun's rays to pass through and maintain the earth's temperature otherwise the earth will become too cold to sustain lives.
