Question

question 11 (1 point)
(02.02 lo)
which of the following groups of elements are likely to have substances that have both metallic and non - metallic properties?

a actinides

b group 18

c lanthanides

d group 14

question 12 (1 point)
(02.02 mc)
the atomic number of an element is 12. based on its electron arrangement, which of the following explains its correct position in the periodic table?

a group 3, because it has two electrons in the 3p orbital

b group 2, because it has two electrons in the 3p orbital

c group 3, because its last electron is in the 3p orbital

d group 2, because its last electron is in the 2p orbital

Explanation:

Question 11

Elements with both metallic and non - metallic properties are metalloids. Group 14 contains elements like silicon and germanium which are metalloids. Actinides and lanthanides are mostly metals, and Group 18 elements (noble gases) are non - metals. So the group with elements likely to have substances with both metallic and non - metallic properties is Group 14.

The atomic number of the element is 12, so the element is magnesium (Mg). The electron configuration of Mg is $1s^{2}2s^{2}2p^{6}3s^{2}$. The number of valence electrons (electrons in the outermost shell) is 2. Elements in Group 2 have 2 valence electrons. The last electron of Mg is in the 3s orbital, but among the given options, option b (even though the orbital description has a mistake, it is the only one with Group 2 which is correct based on valence electrons) is the closest. Wait, actually, the correct electron configuration shows the last electrons are in 3s, but the options have some errors. But based on the number of valence electrons (2), the element should be in Group 2. Among the options, option b says Group 2, because it has two electrons in the 3p orbital (this is incorrect about the orbital, but the group number is correct based on valence electrons). So the answer is b.

Answer:

d. Group 14

Question 12