What is an element? O Substances that can be separtated by physical chemical means.

O Simplest form of matter.

O The smallest unit of an element that maintains the chemial identity of the element.

O Contains more than one kind of particle.

Scientists often deal with numbers that are either very large or very small. for example, the radius of the sun is approximately 696,000 kilometers, while bacterial cells are as small as 1.9 × 10-4 millimeters. express each of these numbers in an alternate form.