d and f BLOCK ELEMENTS

What does a positive electron gain enthalpy indicate?

• Energy is released when an electron is added to the atom.
• Energy must be supplied to add an electron to the atom.
• The atom readily gains an electron.
• The atom forms a positive ion easily.

What is the general trend for first ionization enthalpy down a group?

• It generally increases.
• It generally decreases.
• It remains constant.
• It first increases then decreases.

What is the general trend for electron gain enthalpy across a period from left to right?

• It generally becomes less negative (less exothermic).
• It generally becomes more negative (more exothermic).
• It remains constant.
• It becomes positive.

Which element among I-VI is most likely to be a halogen?

• Element I
• Element III
• Element IV
• Element VI

Which element among I-VI is most likely to be an alkaline earth metal?

• Element I
• Element II
• Element IV
• Element VI