---

Question 1:

Who is credited with the development of the periodic table?

A) Dmitri Mendeleev
B) Marie Curie
C) Albert Einstein
D) Isaac Newton

Show Answer

Explanation: The correct answer is A) Dmitri Mendeleev. Dmitri Mendeleev is credited with the development of the periodic table in the 1860s. He organized the elements based on their properties and predicted the existence and properties of undiscovered elements.

---

Question 2:

The elements in the periodic table are arranged in order of increasing:

A) Atomic mass
B) Atomic number
C) Number of valence electrons
D) Electronegativity

Show Answer

Explanation: The correct answer is B) Atomic number. The elements in the periodic table are arranged in order of increasing atomic number. The atomic number corresponds to the number of protons in an atom's nucleus and determines the element's identity.

---

Question 3:

Elements in the same group or column of the periodic table have:

A) Similar chemical properties
B) Similar atomic masses
C) Similar atomic radii
D) Similar electronegativities

Show Answer

Explanation: The correct answer is A) Similar chemical properties. Elements in the same group or column of the periodic table have similar chemical properties. This similarity arises due to their similar outer electron configurations, which determine the elements' reactivity and bonding behavior.

---

Question 4:

What is the group number of noble gases in the periodic table?

A) Group 1
B) Group 2
C) Group 17
D) Group 18

Show Answer

Explanation: The correct answer is D) Group 18. Noble gases, also known as inert gases, are found in Group 18 of the periodic table. These gases include helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). Noble gases have full valence electron shells and are chemically unreactive.

---

Question 5:

The lanthanides and actinides are located in which region of the periodic table?

A) Period 6
B) Group 1
C) Transition metals
D) Inner transition metals

Show Answer

Explanation: The correct answer is D) Inner transition metals. The lanthanides and actinides, also known as the rare earth elements, are located in the inner transition metals region of the periodic table. These elements are placed below the main body of the periodic table and occupy two rows: the lanthanide series (Period 6) and the actinide series (Period 7).