Question

1. which element has a 3p sublevel that contains 3 electrons?

a) phosphorus b) sulfur
c) chlorine d) argon

1. which element has a 4s sublevel with 2 electrons for its outermost electrons?

a) calcium b) magnesium
c) beryllium d) strontium

1. which element has 1 electron in its 3d sublevel?

a) scandium b) titanium
c) vanadium d) chromium

1. which element has 5 electrons in its 5p sublevel?

a) iodine b) xenon
c) tellurium d) antimony

1. which element has a completely filled 3p sublevel for its outermost electrons?

a) argon b) neon
c) krypton d) xenon

1. which element has 2 electrons in its 6p sublevel?

a) lead b) bismuth
c) polonium d) thallium

1. which principal quantum number is used to determine the row of an element on the periodic table?

a) the number of protons in the nucleus b) the number of neutrons in the nucleus
c) the principal quantum number of the outermost electrons d) the atomic mass of the element

Explanation:

1. For Q14: Use electron configuration. Phosphorus has config $1s^22s^22p^63s^23p^3$, so 3p has 3 electrons.
2. For Q15: Check outer electron config. Strontium is in group 2, period 5, config $[Kr]5s^2$; its outermost is 5s? Correction: Wait, 4s is period 4 group 2: Calcium is $[Ar]4s^2$, so outermost 4s has 2 electrons.
3. For Q16: Scandium has config $[Ar]4s^23d^1$, so 3d has 1 electron.
4. For Q17: Iodine has config $[Kr]4d^{10}5s^25p^5$, so 5p has 5 electrons.
5. For Q18: Argon has config $1s^22s^22p^63s^23p^6$, so 3p is fully filled as outermost.
6. For Q19: Lead has config $[Xe]4f^{14}5d^{10}6s^26p^2$, so 6p has 2 electrons.
7. For Q20: The row (period) of an element matches the principal quantum number of its outermost valence electrons.

Answer:

1. a) Phosphorus
2. a) Calcium
3. a) Scandium
4. a) Iodine
5. a) Argon
6. a) Lead
7. c) The principal quantum number of the outermost electrons