Question

1. which trends are observed as each of the elements within group 15 on the periodic table is considered in order from top to bottom?

a. their metallic properties decrease, and their atomic radii decrease.
b. their metallic properties decrease, and their atomic radii increase.
c. their metallic properties increase, and their atomic radii decrease.
d. their metallic properties increase, and their atomic radii increase.

1. the group 17 element with the highest electronegativity is

a. iodine.
b. fluorine.
c. chlorine.
d. bromine.

1. what occurs when an atom of chl a chloride ion?

a. the chlorine atom loses an electron radius becomes larger.
b. the chlorine atom gains an electron, radius becomes larger.
c. the chlorine atom gains an electron, a radius becomes smaller.
d. the chlorine atom loses an electron, ar radius becomes smaller.

1. which of the following elements has the highest ionization energy?

a. barium
b. calcium
c. strontium
d. magnesium

1. which element in group 18 of the periodic table has the highest first ionization energy?

a. ar
b. he
c. ne
d. kr

Explanation:

• Question 5: As we move down Group 15 (Nitrogen group), the number of electron shells increases. This leads to an increase in atomic radius. Also, metallic character increases down a group as elements tend to lose electrons more easily.
• Question 6: Fluorine has the highest electronegativity among Group 17 (Halogens) elements. This is because it has a small atomic size and a high nuclear charge, which strongly attracts electrons.
• Question 7: A chlorine atom gains an electron to form a chloride ion. When an atom gains an electron, the electron - electron repulsion increases, and the effective nuclear charge per electron decreases, causing the radius to become larger.
• Question 8: Magnesium has the highest ionization energy among the given elements (barium, calcium, strontium, magnesium). Ionization energy decreases down a group. Magnesium is higher up in Group 2 compared to the other elements.
• Question 9: Helium (He) has the highest first ionization energy in Group 18 (Noble gases). Ionization energy decreases down a group. Helium is at the top of Group 18.

Answer:

1. D. Their metallic properties increase, and their atomic radii increase.
2. B. fluorine.
3. B. The chlorine atom gains an electron, radius becomes larger.
4. D. magnesium
5. B. He