Question

does oxygen belong? group 2
c. what group does chlorine belong? group 17
6.) which of the following will have a larger radius than zinc? gallium, aluminum, magnesium, strontium?
7.) the atomic radius across period: a. decrease from left to right b. increase from left to right c. stay the same
as you move down a group on the periodic table, what... they get larger c. they get smaller
which element has the...
what peri...

Explanation:

Question 6: What group does Chlorine belong?

Chlorine (Cl) has an atomic number of 17. The electron configuration of Chlorine is $1s^2 2s^2 2p^6 3s^2 3p^5$. The number of valence electrons (electrons in the outermost shell) determines the group. Chlorine has 7 valence electrons. In the periodic table, elements in group 17 (also known as group VIIA in the old numbering) have 7 valence electrons. These are the halogens. So, Chlorine belongs to group 17.

Step 1: Recall the trend of atomic radius

Atomic radius generally decreases across a period (from left to right) and increases down a group (from top to bottom). Zinc (Zn) is in period 4, group 12.

Step 2: Analyze each option

• Gallium (Ga): It is in period 4, group 13. Since it is to the right of Zinc in the same period, its atomic radius is smaller than Zinc (because atomic radius decreases across a period).
• Aluminum (Al): It is in period 3, group 13. Comparing with Zinc (period 4), as we move up a group, atomic radius decreases. So Aluminum has a smaller radius than Zinc.
• Magnesium (Mg): It is in period 3, group 2. Similar to Aluminum, it is in a higher period (period 3 vs period 4 of Zinc) and to the left, but the decrease in radius due to moving up a period is significant. So Magnesium has a smaller radius than Zinc.
• Strontium (Sr): It is in period 5, group 2. Since it is below Zinc (in a lower period, moving down a group), atomic radius increases down a group. So Strontium has a larger atomic radius than Zinc.

As we move from left to right across a period in the periodic table, the number of protons in the nucleus increases (atomic number increases). The electrons are added to the same principal energy level (same shell). The increased positive charge of the nucleus pulls the electrons more strongly towards the nucleus, resulting in a decrease in the atomic radius. So the atomic radius decreases from left to right across a period.

Answer:

Group 17 (or VIIA)

Question 7: Which of the following will have a larger radius than Zinc? (Options: Gallium, Aluminum, Magnesium, Strontium)