PHYSICAL SCIENCE

5. A state of matter consisting of ______ gas
7. Mass, the weighted average of the atomic ______ of an element's isotopes
10. Number, the number of protons and ______ in an atom's nucleus
11. Bond, a type of chemical bond formed through the electrostatic attraction between ______ charged ions
13. Atoms of the same element with different numbers of ______
14. A row in the ______ table
16. The capacity of an atom to ______ with other atoms
17. The central part of an atom containing ______ and neutrons
20. Fusion, the process by which light nuclei combine to form a ______ nucleus
21. Cell, the smallest repeating unit in a crystal ______
23. Number, the number of ______ in an atom's nucleus
24. Energy, the energy required to remove an ______ from an atom
26. The spontaneous emission of particles or ______ from an unstable nucleus
27. Formula, a representation of a molecule showing how the atoms are ______
29. Negatively charged particle orbiting the ______

1. A column in the periodic table representing elements with similar ______
2. Of elements, the process of creating heavier elements from ______ ones
3. Theory, the theory that all matter is composed of ______
4. Fission, the process by which a nucleus ______ into two or more smaller nuclei
6. Bond, a chemical bond formed by the ______ of electrons
8. Orbital, a region around the nucleus where an electron is likely to be ______
9. The smallest particle of a compound that retains its chemical ______
12. A charged ______ or molecule
15. Configuration, the arrangement of electrons around the ______ of an atom
17. A particle with no ______ in the nucleus of an atom
18. The ability of an atom to attract ______ in a chemical bond
19. Table, the chart that organizes elements by atomic ______ and properties
22. A substance that cannot be ______ down into simpler substances by chemical means
25. The smallest ______ of an element
28. A positively charged ______ in the nucleus of an atom