Question

1. which element below belongs to the noble gas family?

a) group 1 period 3 \tc) group 17 period 4
b) group 2 period 6 \td) group 18 period 3

1. which pair of elements would be the most reactive?

a) li and na
b) be and sr
c) cl and br
d) he and ne

1. study the table below:

atom	number of protons	number of neutrons	number of electrons
b	11	12	11
c	40	91	40
d	54	77	54

based off of the above table, which atom is the most reactive?
a) a
b) b
c) c
d) d

extra exploration:

1. (review from yesterday)

which pair of elements will react similarly to other elements?
a) al and ce
b) al and ga
c) ce and ge
d) ga and as

1. the figure below represents the periodic table and the location of four different elements on the table.

which statement is true about the above periodic table?
a) element y and z have similar chemical properties
b) elements w, x, y and z are halogens and are very reactive
c) elements w, x, y and z are noble gases and are not reactive at all
d) element y has a higher atomic number than element z

Explanation:

Question 2

Noble gases are in Group 18 of the periodic table. So we check each option:

• a) Group 1 period 3: Group 1 is alkali metals, not noble gases.
• b) Group 2 period 6: Group 2 is alkaline earth metals, not noble gases.
• c) Group 17 period 4: Group 17 is halogens, not noble gases.
• d) Group 18 period 3: Group 18 is noble gas group, so this element belongs to noble gas family.

Reactivity: Alkali metals (Group 1) and halogens (Group 17) are highly reactive. Let's analyze each pair:

• a) Li and Na: Both are Group 1 (alkali metals), highly reactive.
• b) Be and Sr: Group 2 (alkaline earth metals), less reactive than Group 1.
• c) Cl and Br: Group 17 (halogens), reactive but alkali metals are more reactive in general (or compare reactivity trends: for Group 1, reactivity increases down the group; for Group 17, reactivity decreases down the group. Li and Na are more reactive than Cl and Br).
• d) He and Ne: Noble gases, non - reactive.

Among the options, Li and Na (Group 1) are the most reactive.

First, determine the element for each atom:

• Atom A: Protons = 6, so element is C (carbon). Carbon is non - metal, relatively less reactive.
• Atom B: Protons = 11, element is Na (sodium). Sodium is Group 1 (alkali metal), highly reactive.
• Atom C: Protons = 40, element is Zr (zirconium), a transition metal, less reactive than alkali metals.
• Atom D: Protons = 54, element is Xe (xenon), a noble gas, non - reactive.

So the most reactive atom is B.

Answer:

d) Group 18 period 3

Question 3