1. .1
How did Mendeleev arrange the known chemical elements in his Periodic Table?
Atomic Mass.

2. How many valence electrons do all halogens have?.2
How many valence electrons do all halogens have? 7

3. On a periodic table, the vertical columns are called ___________.3
On a periodic table, the vertical columns are called ___________.
Groups or families.

4. Which element in group 1A is most reactive?4.
Which element in group 1A is most reactive?
Francium

5. How many valance electrons do all alkali metals have?5.
How many valance electrons do all alkali metals have? 1.

6. On the periodic table, how is an element’s atomic mass calculated?6.
On the periodic table, how is an element’s atomic mass calculated?
The weighted average of all the isotopes of the element as found in nature.

7. How can you tell from the periodic table if an element is a metal?7.
How can you tell from the periodic table if an element is a metal?
Metals are to the left of the stair-step line.

8. Where in the periodic table are the most reactive metals found?8.
Where in the periodic table are the most reactive metals found?
Group 1A and Group 7A.

9. Which of these elements is in the lanthanide series?9.
Which of these elements is in the lanthanide series?
Hafnium, Bohrium, Erbium,
Mendelevium, or Polonium
Erbium.

10. 10.
What increases by exactly one as you move from left to right across a period?
Atomic number, the number of protons the element has.

11. What are the two most reactive elements in period 3?
11.
What are the two most reactive elements in period 3?
Sodium and Chlorine.

12. On a periodic table, the horizontal rows are called ___________.
12.
On a periodic table, the horizontal rows are called ___________.
Periods

13. What are the characteristics of a metal?
13.
What are the characteristics of a metal?
Shiny luster, solid at room temperature, malleable, ductile, good conductor of heat and electricity.

14. Which element in group 7A is least reactive?
14.
Which element in group 7A is least reactive?
Astatine.

15. 15.
Mendeleev’s Periodic Table was shown to be accurate because it predicted ____________.
The existence and properties of undiscovered elements.

16. At room temperature what state of matter are metals?
16.
At room temperature what state of matter are metals?
Solid except for mercury which is a liquid.

17. How many valence electrons do the most reactive elements have?
17.
How many valence electrons do the most reactive elements have?
1 or 7.

18. 18
How does the number of valence electrons change moving across the periodic table from left to right?
Increases by 1 in the A groups

19. What do the halogens have that the alkali metals don’t have?
19.
What do the halogens have that the alkali metals don’t have?
More valence electrons (7 instead of 1).

20. Why are the noble gases unlikely to react with other elements?20
Why are the noble gases unlikely to react with other elements?
.They have 8 valence electrons. Their outer energy level is full.

21. What determines if an element is likely to react chemically?21
What determines if an element is likely to react chemically?
The number of valence electrons

22. How many valence electrons does boron have?
22.
How many valence electrons does boron have? 3.

23. Which element in group 1A is least reactive?
23.
Which element in group 1A is least reactive?
Lithium.

24. How does the reactivity of alkali metals change moving down the group?
24.
How does the reactivity of alkali metals change moving down the group?
Moving down the group, the alkalis become more reactive.

25. How does the reactivity of the halogens change moving up the group?
25.
How does the reactivity of the halogens change moving up the group?
Moving up the group, halogens become more reactive.

26. What state of matter are all of the elements in group VIII A?
26.
What state of matter are all of the elements in group VIII A?
gas.

27. Where in the periodic table are the most reactive non-metals found?
27.
Where in the periodic table are the most reactive non-metals found?
Group 7A.

28. Why are highly reactive elements stored in argon or other noble gases?
28.
Why are highly reactive elements stored in argon or other noble gases?
Noble gases don’t react with anything

29. What element is found in most compounds in your body but not in water?
29.
What element is found in most compounds in your body but not in water?
Carbon

30. How many valence electrons do all alkaline metals have?
30.
How many valence electrons do all alkaline metals have? 2.

31. Where are the metalloids found?
31.
Where are the metalloids found?
Touching the stair-step line except for aluminum which is a metal

32. 32.
What is the maximum number of electrons that the third energy level can hold?
n 2

33. Where would you find an element with two valence electrons?
33.
Where would you find an element with two valence electrons?
Group 2A…Alkaline Earth Metals

34. What is the group number and period number for Chlorine?
34.
What is the group number and period number for Chlorine?
Group 7A and Period 3.

35. Is hydrogen a metal or a non-metal?
35.
Is hydrogen a metal or a non-metal?
A non metal.

36. Which of the following is a transition metal?
36.
Which of the following is a transition metal?
Barium, copper, aluminum, uranium, radon
.Copper

37. What is used to define an atomic mass unit?
37.
What is used to define an atomic mass unit?
1/12 of the mass of a Carbon-12 atom.

38. How many valence electrons do all of the noble gases have?
38.
How many valence electrons do all of the noble gases have? .8

39. Which element in group 7A is most reactive?
39.
Which element in group 7A is most reactive?
Fluorine.

40. How are highly reactive elements stored to prevent them from reacting?
40.
How are highly reactive elements stored to prevent them from reacting?
In noble gases because they don’t react with anything