1. All the matter in the familiar states of solid, liquid or gas is made of substances called __________elements that cannot be broken down further.
2. In other words, __________an element is one of more than one hundred substances that are the basic ingredients of matter.
3. A compound contains two or more __________ elements.
4. __________An atomis the basic unit of a chemical element.
5. __________A molecule is the basic unit of a compound.
6. The part of an atom that has a positive charge is called __________a proton .
7. The part of an atom that has a negative charge is called __________an electron.
8. __________A neutron is the part of an atom that has no charge—in other words, it is neutral.
9. The smaller parts of atoms are called __________subatomic particles.
10. The __________nucleus is the part of an atom where protons and neutrons are located, and __________orbitals are the parts of an atom where electrons are located.
11. An element’s atomic number tells you the number of __________protons in each atom.
12. You can subtract the atomic number from the atomic weight to find the number of __________neutrons in each atom of an element.
13. Forms of the same element that have equal numbers of protons but different numbers of neutrons are called __________isotopes.
14. The __________chemical symbol is an abbreviation of an element’s name.