Question 1

Which of the following statements best explains why atomic radius increases as you move down a group in the periodic table?

Accepted Answer

Electrons are added to higher principal energy levels, increasing the average distance from the nucleus.

Question 2

Which atom's valence electrons experience the greatest effective nuclear charge: Mg, Al, or S?

Accepted Answer

The valence electrons in S

Question 3

What is the correct formula for calculating the effective nuclear charge ($$Z_{eff}) $$experienced by a valence electron?

Accepted Answer

$$Z_{eff} = Z - S$$

Question 4

Which of the following elements has the smallest atomic radius: S, Ca, F, Rb, or Si?

Accepted Answer

F

Question 5

Why are cations generally smaller than their corresponding neutral atoms?

Accepted Answer

Cations have lost electrons, resulting in a higher effective nuclear charge experienced by the remaining electrons.

Question 6

Which of the following ions is largest among isoelectronic species: $$O^{2-}$$, $$F^{-}$$, $$Na^{+}$$, $$Mg^{2+}$$?

Accepted Answer

$$O^{2-}$$

Question 7

Which of the following electron configurations is paramagnetic?

Accepted Answer

$$[Ar]4s^2$ 3d^6$

Question 8

A neutral atom of Fe has the electron configuration $$[Ar]4s^2$ 3d^6$. What is the electron configuration of Fe$$^{3+}$$?

Accepted Answer

$$[Ar]3d^5$

Question 9

Which of the following best describes the trend in first ionization energy as you move across a period from left to right?

Accepted Answer

It increases due to increasing effective nuclear charge.

Question 10

Which element has a higher first ionization energy: Al or S? Explain using periodic trends.

Accepted Answer

S, because it is to the right of Al in the same period and experiences a higher effective nuclear charge.

Question 11

Which of the following ions is diamagnetic?

Accepted Answer

$$N^{3-}$$

Question 12

Why are anions generally larger than their corresponding neutral atoms?

Accepted Answer

Anions have gained electrons, resulting in a lower effective nuclear charge per electron.

Question 13

Arrange the following elements in order of decreasing atomic radius: S, Ca, F, Rb, Si.

Accepted Answer

Rb \u003e Ca \u003e Si \u003e S \u003e F

Question 14

Which of the following best explains why the atomic radii of transition metals are roughly the same size across the d block?

Accepted Answer

The effective nuclear charge on the ns electrons remains approximately the same.

Question 15

Which of the following elements has the highest first ionization energy: O, F, N, or C?

Accepted Answer

F

Question 16

Which of the following is true about the magnetic properties of atoms?

Accepted Answer

Atoms with unpaired electrons are paramagnetic and attracted to a magnetic field.

Question 17

For isoelectronic species, which has the smallest radius: $$N^{3-}$$, $$O^{2-}$$, $$F^{-}$$, $$Na^{+}$$?

Accepted Answer

$$Na^{+}$$

Question 18

Which of the following best describes the trend in atomic radius as you move across a period from left to right?

Accepted Answer

Atomic radius decreases due to increased effective nuclear charge.

Question 19

Which of the following best explains why the first ionization energy decreases as you move down a group?

Accepted Answer

Valence electrons are farther from the nucleus and held less tightly.

Question 20

Which of the following elements would you expect to have the largest atomic radius: Ge, Al, or Si?

Accepted Answer

Ge

lecture 12

스터디 가이드 - 연습 문제