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State and explain the general trend in the first ionisation energies of the Period 2 elements Lithium to Fluorine.

The general trend is that the first ionisation energies increase across the period.First ionisation energies increase across the period as from Lithium to Fluorine the nuclear charge is increasing yet the at...
AM
Answered by Alice M. • Chemistry tutor
6127 Views

How do I form the imperfect?

The imperfect tense is used for ongoing actions (e.g. was doing) or actions done regularly in the past (e.g. used to do). It is formed by taking the endings off a verb to form its "stem". For -ar v...
ZA
Answered by Zain A. • Spanish tutor
1897 Views

Explain why the first ionisation energy of barium is less than the first ionisation energy of calcium.

Barium is in the sixth period, Calcium is in the fourth. Therefore, Barium experiences more shielding, resulting in weaker attraction of the nucleus for outermost electrons.
JF
Answered by Joseph F. • Chemistry tutor
5722 Views

Explain why a smoke alarm works by emitting and detecting alpha radiation instead of gamma or beta radiation.

Alpha radiation isn't very penetrating and so is absorbed and stopped by smoke particles. This causes a change in count rate when there is smoke present. This change in count rate allows the alarm to be trig...
FM
Answered by Fin M. • Physics tutor
11960 Views

‘1789, 1848, 1917...’ Is there a logic to this sequence?

"Revolutions are like earthquakes." The words of Jack Goldstone allows us to view revolutions as unpredictable and complex processes. He argues that when they occur, they can often be a shock to ev...
AC
2701 Views