Periodic Table and Periodic Trends

As you move down a group, atomic radius increases because - 

• you add more and more neutrons

• you add more and more protons

• you add more and more shells (energy levels)

• you add more atomic mass

Answer explanation

As you move down a group in the periodic table, you add more shells (energy levels) of electrons. This increase in shells leads to a larger atomic radius, as the outermost electrons are farther from the nucleus.

The atom with the largest atomic radius in Group 18 is - 

• Ar

• He

• Kr

• Rn

Answer explanation

Rn (Radon) has the largest atomic radius in Group 18 because atomic radius increases down a group due to the addition of electron shells. Rn is the heaviest noble gas, resulting in a larger radius compared to Ar, He, and Kr.

for each new energy level, the valence electrons are in a higher

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As you move across the periodic table from left to right, the atomic radius decreases.  This is because - 

• the number of protons increases, so attraction to electrons increases

• the number of energy levels increases

• the number of electrons increases

• the atomic mass increases

Answer explanation

As you move across the periodic table from left to right, the number of protons increases, enhancing the positive charge in the nucleus. This increased attraction pulls electrons closer, resulting in a smaller atomic radius.

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The atom with the largest atomic radius in Period 4 (row 4) is - 

• K

• Kr

• Fe

• Fe

Answer explanation

In Period 4, atomic radius increases down the group. Potassium (K) is in Group 1 and has the largest atomic radius due to having fewer protons and a larger electron cloud compared to Kr and Fe, making it the correct answer.

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Francium (Fr) has the lowest ionization energy in Group 1 because - 

• it has the smallest number of valence electrons

• it has the greatest atomic mass

• it has the greatest number of protons, so it attracts its electrons the strongest

• its 1 valence electron is very far from the nucleus, so little energy is needed to remove it

Answer explanation

Francium has its only valence electron far from the nucleus, resulting in a weak attraction to the nucleus. This makes it easier to remove the electron, leading to the lowest ionization energy in Group 1.

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The element with the smallest ionization energy in Period 6 is - 

• Rn

• Cs

• Os

• Tm

Answer explanation

The element with the smallest ionization energy in Period 6 is Cs (cesium). As you move down a group in the periodic table, ionization energy decreases due to increased atomic size and shielding effect, making it easier to remove an electron.

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As you move across the periodic table atoms tend to get smaller because, ______________.

• the atoms have more mass.

• the atoms have less mass

• the atoms have more protons.

• the atoms have less electrons.

Answer explanation

As you move across the periodic table, atoms have more protons, which increases the positive charge in the nucleus. This stronger attraction pulls electrons closer, resulting in smaller atomic size.

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The energy required to remove electrons is the definition of: 

• Electronegativity

• Atomic Number

• Atomic Radius

• Ionization

Answer explanation

The energy required to remove electrons from an atom is known as ionization energy. Therefore, the correct answer is ionization, as it specifically refers to the process of removing electrons.

What is the name of family I

• Alkaline Earth Metals
• Boron Family
• Alkali Metals
• Halogen Family