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Ions, isotopes, oxidation numbers, and valence electrons

1. tool for teachers Atoms that have the same name, atomic number, proton, number, and electron number but different neutron number and mass number are called
isotopes, reactive atoms build your own quiz , ions, unstable atoms
2. The highest number of valence electrons an element can have is
2 mix questions , 4, 6, 8
3. class website Valence electrons are located
in the innermost energy level, in the outermost energy level, in the middle energy level, in more than one energy level
4. A hydrogen atom has
1 valence electron, 2 valence electrons, 3 valence electrons, 4 valence electrons
5. The octet rule states that atoms are normally stable when their outer energy levels are
empty, full, half full, 3/4 full
6. Alkali metals all have an oxidation number of
1%2b, 2%2b, 2-, 0
7. Alkaline-earth metals all have an oxidation number of
1%2b online quizzes , 2%2b, 3%2b, 3-
8. Elements in the nitrogen group usually have an oxidation number of
1%2b, 2%2b, 3-, 4%2b/-
9. Elements with oxidation numbers of zero are
alkali metals, oxygen group teacher , halogens, noble gases
10. Halogens have how many valence electrons?
2, 4 interactive learning , 7, 8
11. Halogens usually have what oxidation number?
1%2b, 2%2b, 4%2b/-, 1-
12. Elements in the carbon group usually have what oxidation number?
1%2b, 4%2b/-, 2-, 0
13. Transition metals usually have what oxidation number?
1%2b, 4%2b/-, 2-, It varies.
14. results history Uranium-235 and uranium-238 have different
atomic numbers, proton numbers, neutron numbers, oxidation numbers
15. Elements in the same group have the same number of
protons, neutrons, valence electrons, total electrons
16. Valence electrons are important because they determine the ________ of an element.
chemical properties, mass, atomic number, color
17. There are ___ periods of elements, which means that there are ___ energy levels of electrons.
9, 18, 18, 7, 18, 18, 7, 7
18. Which isotope of carbon is the most common?
carbon-11, carbon-12, carbon-13, carbon-14
19. Elements with 3 valence electrons are in the ______ group.
boron, carbon, nitrogen, oxygen
20. When elements gain or lose valence electrons, they end up with the same number of electrons as the nearest
alkali metal, transition metal, halogen, noble gas
21. Elements gain or lose electrons in order to become
lighter, heavier, more stable, more dense
22. The oxidation number of a metal is equal to the number of
electrons it gains, electrons it loses results history , protons in the nucleus, neutrons in the nucleus
23. Helium, argon, and krypton do not gain or lose electrons because they are
already stable, already unstable, already neutral, gases