Dating rocks by radioactivity

Radiometric dating is possible because the radioactive decay of large numbers of radioactive atoms follows a predictable pattern.

This predictability allows scientists to measure the age of an object if they can work out how many radioactive atoms were originally present.

By dating these surrounding layers, they can figure out the youngest and oldest that the fossil might be; this is known as "bracketing" the age of the sedimentary layer in which the fossils occur.

And once that first kernel pops, it will never be a kernel again..is forever changed! ) Teaching example using popcorn to teach radioactive decay "A variety of a chemical element (strictly, of one particular element) which is distinguished from the other varieties of the element by a different mass number but shares the same atomic number and chemical properties (and so occupies the same position in the periodic table)." That definition may not mean anything to them.

The biggest assumption is that, to first order, the number of asteroids and comets hitting the Earth and the Moon was the same as for Mercury, Venus, and Mars. The bottom line is that the more craters one sees, the older the surface is.

This can be interpreted in two ways: why it is important to know the age of a planet or how is age dating important in determining the age of a planet?

If they can begin to comprehend that it is random and spontaneous, they end up feeling less nervous about the whole thing.

Radioactive decay involves the spontaneous transformation of one element into another.