Chapter 1: Periodic table, Multiple choice

Question 1

1. What are the horizontal rows in the periodic table called?
   A) Groups
   B) Periods
   C) Families
   D) Columns

Answer 1

B) Periods

Question 2

2. What does each period in the periodic table represent?
   A) The number of protons in an atom
   B) The number of electron shells in an atom
   C) The atomic mass of elements
   D) The number of neutrons in an atom

Answer 2

B) The number of electron shells in an atom

Question 3

3. What are the vertical columns in the periodic table called?
   A) Periods
   B) Groups
   C) Rows
   D) Layers

Answer 3

B) Groups

Question 4

4. Why do elements in the same group share similar chemical properties?
   A) They have the same atomic mass
   B) They have the same number of neutrons
   C) They have the same number of electrons in their outermost shell
   D) They have the same atomic number

Answer 4

C) They have the same number of electrons in their outermost shell

Question 5

5. Which of the following is an example of a metal?
   A) Oxygen (O)
   B) Carbon (C)
   C) Gold (Au)
   D) Nitrogen (N)

Answer 5

C) Gold (Au)

Question 6

6. What is a common property of non-metals?
   A) They are shiny and malleable
   B) They are good conductors of electricity
   C) They tend to form gases or brittle solids
   D) They are generally ductile

Answer 6

C) They tend to form gases or brittle solids

Question 7

Which element is a metalloid?
A) Iron (Fe)
B) Silicon (Si)
C) Sodium (Na)
D) Nitrogen (N)

Answer 7

B) Silicon (Si)

Question 8

8. What does the atomic number of an element represent?
   A) The average mass of isotopes
   B) The number of neutrons in an atom
   C) The number of protons in the nucleus
   D) The total number of electrons

Answer 8

C) The number of protons in the nucleus

Question 9

9. What is the atomic mass of an element?
   A) The mass of a single isotope
   B) The average mass of all isotopes of an element
   C) The mass of the nucleus only
   D) The total number of protons and neutrons

Answer 9

B) The average mass of all isotopes of an element

Question 10

10. What group do sodium (Na) and potassium (K) belong to?
    A) Noble Gases
    B) Halogens
    C) Alkali Metals
    D) Transition Metals

Answer 10

C) Alkali Metals

Question 11

11. Which of the following elements is a noble gas?
    A) Sodium (Na)
    B) Helium (He)
    C) Chlorine (Cl)
    D) Iron (Fe)

Answer 11

B) Helium (He)

Question 12

12. What element are organic molecules primarily constructed from?
    A) Nitrogen
    B) Oxygen
    C) Carbon
    D) Sulfur

Answer 12

C) Carbon

Question 13

13. Which types of bonds are important for understanding the structure and bonding of organic molecules?
    A) Hydrogen bonds and metallic bonds
    B) Ionic bonds and covalent bonds
    C) Covalent bonds and van der Waals forces
    D) Ionic bonds and hydrogen bonds

Answer 13

B) Ionic bonds and covalent bonds

Question 14

14. What is the main reason atoms form ionic or covalent bonds?
    A) To increase their mass
    B) To achieve filled electron shells and a stable noble gas configuration
    C) To reduce their size
    D) To become reactive

Answer 14

B) To achieve filled electron shells and a stable noble gas configuration

Question 15

15. In a covalent bond, which atom typically has greater electron density?
    A) The less electronegative atom
    B) The more electronegative atom
    C) Both atoms equally
    D) Neither atom

Answer 15

B) The more electronegative atom

Question 16

16. What scale is used to compare the electronegativities of bonded atoms?
    A) The Lewis scale
    B) The Pauling electronegativity scale
    C) The Dalton scale
    D) The Avogadro scale

Answer 16

B) The Pauling electronegativity scale

Question 17

17. What is the maximum number of electrons that can be accommodated in the 2p orbitals?
    A) 2
    B) 4
    C) 6
    D) 8

Answer 17

C) 6

Question 18

18. In what order are electrons added to atomic orbitals as atomic number increases?
    A) 1s, 3s, 2p, 2s, 3p
    B) 1s, 2s, 2p, 3s, 3p
    C) 1s, 2p, 2s, 3s, 3p
    D) 1s, 3p, 2s, 2p, 3s

Answer 18

B) 1s, 2s, 2p, 3s, 3p

Question 19

19. What type of molecular orbitals are formed by end-on overlap of atomic orbitals?
    A) π molecular orbitals
    B) σ molecular orbitals
    C) δ molecular orbitals
    D) φ molecular orbitals

Answer 19

B) σ molecular orbitals

Question 20

20. What is Hückel’s rule associated with?
    A) The number of carbon atoms in a ring
    B) The total number of π electrons
    C) The hybridization of atoms
    D) The type of bonds formed

Answer 20

B) The total number of π electrons

Question 21

21. According to Hückel’s rule, how many π electrons will make a compound aromatic?
    A) 4n
    B) 4n + 2
    C) 6n
    D) 2n + 1

Answer 21

B) 4n + 2

Question 22

22. Which of the following compounds is an example of an aromatic compound?
    A) Ethylene
    B) Benzene
    C) Cyclohexane
    D) Propylene

Answer 22

B) Benzene

Question 23

23. What type of hybridization do nitrogen atoms have in pyridine?
    A) sp
    B) sp²
    C) sp³
    D) sp²

Answer 23

B) sp²