Group 13 Elements Properties and Trends

The video tutorial covers the elements of the boron family, also known as Group 13, which includes boron, aluminium, gallium, indium, and thallium. It discusses their electron configurations, atomic and ionic radii, and the trends observed in these properties. The video also examines the melting points and crystal structures of these elements, highlighting the unique characteristics of boron and gallium. Additionally, it explores the metallic and electropositive character trends, as well as the density trends within the group, noting exceptions like aluminium.

Which element in the boron family has an atomic number of 31?

• Boron

• Aluminium

• Thallium

• Gallium

What is the electronic configuration of aluminium?

• Krypton core plus 4d10 5s2 5p1

• Helium core plus 3s2 3p1

• Argon core plus 3d10 4s2 4p1

• Neon core plus 3s2 3p1

Why is the atomic radius of gallium smaller than that of aluminium?

• Due to a larger number of protons

• Due to a smaller number of electrons

• Due to ineffective shielding by d orbitals

• Due to effective shielding by d orbitals

How do the atomic and ionic radii of group 13 elements compare to those of group 2?

• Unpredictable

• Smaller

• Larger

• Equal

What is the trend in melting points from boron to thallium in group 13?

• Decrease then increase

• Increase then decrease

• Constant

• Irregular

Why does boron have a high melting point?

• Due to its low atomic mass

• Due to its diatomic molecules

• Due to its icosahedral structure

• Due to its closed pack structure

Which element in group 13 has the highest metallic character?

• Boron

• Thallium

• Aluminium

• Indium

What happens to the electropositive character from aluminium to thallium?

• Decreases

• Increases

• Fluctuates

• Remains constant

What is the general trend in density as you move down group 13?

• Increases

• Decreases

• Remains constant

• Fluctuates

Which element in group 13 is an exception to the general density trend?

• Gallium

• Boron

• Thallium

• Aluminium