Question 3

Consider the graph of the first ionisation energy and answer the questions that follow.

3.1 Define the term ionisation energy. (2)

3.2 State the general trend in ionisation energy from left to right across a period
on the periodic table. (2)

3.3 There is a drop in ionisation energy from beryllium to boron.

3.3.1 Write down the sp-notation for beryllium AND boron. (4)

3.3.2 Explain this drop in ionisation energy. (3)

3.4 Is the following statement TRUE or FALSE? If false, rewrite the statement correctly.
The ionisation energy of noble gases is high because of the half-filled s- and p-orbitals. (2)

3.5 Study the ionisation energy of the group (I) elements in the graph above and
answer the questions that follow.

3.5.1 Give the general name of the group (I) elements. (1)

3.5.2 State the trend in the reactivity of elements in group (I). (2)

3.5.3 Explain the reason for the trend in QUESTION 3.5.2 by using the
graph of ionisation energy. (2)
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