Answer Key to Elements and the Periodic Table Study Guide

1.  Left hand side

2.  Right hand side

3.  Border the staircase between the metals and nonmetals

4.  Metalloids are elements that have characteristics of both metals and nonmetals.

5.  Noble gases. They do not react with other elements, are gases at room temperature.

6.  Vertical (up and down)

7.  Horizontal (straight across)

8.  The transition metals are groups 3 – 12

9.  Halogens – group 17

10.  Find properties of metals on page 88 in the textbook.

11.  Look at the periodic table to find the answer to this question.

Tungsten (W) would be heavier because it has a larger atomic number. That means that the atoms of tungsten have more protons and neutrons that an atom of cobalt, and therefore would have more mass.

12.  Al (aluminum) and In (Indium).

13.  They are in the same group or family as Ga (gallium) and elements in the same group or family have similar chemical and physical properties.

14.  Se (selenium) atomic number -34 atomic mass – 79

In the nucleus – 34 protons and 45 neutrons.

Remember: atomic number = number of protons

Atomic mass = number of protons + number of neutrons

Electrons are in the electron cloud, not in the nucleus

Element / Atomic # / Atomic Mass / Protons / Neutrons / Electrons
Chlorine / 17 / 35 / 17 / 18 / 17
Silicon / 14 / 28 / 14 / 14 / 14
Potassium / 19 / 39 / 19 / 20 / 19
Nickel / 28 / 59 / 28 / 31 / 28

17. solids

18. gases

19. solids

21. Look up definitions in the textbook

22. metals

23. Noble gases – do not bond with other elements

24. include most the familiar metals, hard and shiny, good conductors, less reactive that groups

1 and 2 (Alkali Metals and Alkaline Earth Metals)

25. the number of protons in an atom, and the number of protons = the number of electrons

26. the sum of the number of protons and neutrons in an atom

27. metals

28. most reactive metals – group 1, Alkali Metals and group 17, Halogens

29. in order of increasing atomic mass 31. The properties of the element - both

30. in order of increasing atomic number chemical and physical – can be predicted.