Question 1

Which scientist is credited with proposing the original periodic law, which states that the properties of elements are a periodic function of their atomic masses?

Accepted Answer

Dmitri Mendeleev

Question 2

Henry Moseley revised the periodic law by arranging elements according to which property?

Accepted Answer

Atomic number

Question 3

Which of the following correctly represents the electron configuration for a neutral atom of sulfur ($$Z = 16$$)?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^6$$\ $$3s^2$$\ $$3p^4$$

Question 4

Which group of elements is designated as the alkali metals according to both the (IA–VIIIA) and IUPAC (1–18) conventions?

Accepted Answer

Group 1 (IA)

Question 5

Within a group in the periodic table, how does atomic size generally change as you move from top to bottom?

Accepted Answer

It increases due to the addition of electron shells.

Question 6

Which of the following elements has the highest ionization energy?

Accepted Answer

Fluorine ($$F)$$

Question 7

Predict the chemical formula for a compound formed between magnesium and chlorine.

Accepted Answer

$$MgCl_2$$

Question 8

Which of the following best explains why elements in the same group have similar chemical properties?

Accepted Answer

They have the same number of valence electrons.

Question 9

What is the predicted ionic charge for a representative element in Group 16 (VIA)?

Accepted Answer

$$-2$$

Question 10

Which of the following elements has the electron configuration ending in $$4p^5$$?

Accepted Answer

Bromine ($$Br)$$

Question 11

If an atom has the electron configuration $$1s^2$$\ $$2s^2$$\ $$2p^6$$\ $$3s^2$$\ $$3p^6$$\ $$4s^1$$, what is the element and its group in the periodic table?

Accepted Answer

Potassium ($$K$$), Group 1 (IA)

Question 12

Which of the following statements about the periodic trends in ionization energy is correct?

Accepted Answer

Ionization energy increases across a period from left to right.

Question 13

A neutral atom of phosphorus ($$P) $$has how many valence electrons?

Accepted Answer

5

Question 14

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

Accepted Answer

Atomic radius decreases due to increasing nuclear charge.

Question 15

Which element is most likely to form a $$+1$$ ion?

Accepted Answer

Sodium ($$Na)$$

Question 16

Given the following electron configuration: $$1s^2$$\ $$2s^2$$\ $$2p^6$$\ $$3s^2$$\ $$3p^6$$\ $$4s^2$$\ $$3d^{10}$$\ $$4p^6$$\ $$5s^2$$\ $$4d^{10}$$\ $$5p^5$$, identify the element.

Accepted Answer

Iodine ($$I)$$

Question 17

Which of the following elements would you expect to have the lowest ionization energy?

Accepted Answer

Cesium ($$Cs)$$

Question 18

A student is asked to predict the formula for a compound formed between aluminum and oxygen. What is the correct formula?

Accepted Answer

$$Al_2O_3$$

Question 19

Which of the following best explains why noble gases are generally unreactive?

Accepted Answer

They have a complete valence shell of electrons.

Question 20

Which of the following elements is in the same period as phosphorus ($$P) $$and has a higher atomic number?

Accepted Answer

Chlorine ($$Cl)$$

Periodic Table and Periodic Trends: Key Concepts and Study Guide

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Study guide - Flashcard