Across
- 2. What is an atom that carries an electrical charge called.
- 4. What has no electrical charge.
- 6. what is the average of the naturally occurring isotopes of an element.
- 9. What is equal to the number of protons plus neutrons.
- 10. What is often used for things that are too small or too large to be observed or that are too difficult to be understood easily.
Down
- 1. What has a positive charge.
- 3. what is the number of protons called.
- 5. What has a negative charge.
- 7. What is two atoms with different number of neutrons called.
- 8. Who discovered the neutron.