Chemistry
Which element from the following has the highest ionisation energy ?
(a) P, Na, Cl
(b) F, O, Ne
(c) Ne, He, Ar
Explain your choice.
Answer
(a) Cl — Among the three elements, Cl is the rightmost in period 3. As ionisation energy increases when moving across a period from left to right hence ionisation energy is highest for Cl.
(b) Ne — It is the rightmost element in period 2 and an inert gas. Hence it has the highest ionisation energy.
(c) He — Ne, He, Ar belong to group 18 and He is at the top. As ionisation energy decreases when moving down the group hence He has the highest ionisation energy.
Related Questions
The atomic number of an element Z is 16. State
(a) the period to which it belongs.
(b) the number of valence electron(s) in the element.
(c) whether the element is a metal or a non-metal.
(d) State the formula of the compound between Z and hydrogen.
M is a metal and its oxide has the formula M2O. This oxide when dissolved in water forms the corresponding hydroxide which is a good conductor of electricity. In the above context, answer the following :
(i) State the number of electrons in the outermost shell of M ?
(ii) Name the group to which M belongs.
(iii) which element has more electronegativity, M or O?
The metals of Group 2 in the periodic table from top to bottom are — Be, Mg, Ca, Sr, and Ba.
(i) Which one of these elements will form ions most readily and why?
(ii) State the common feature in the electronic configuration of all these given elements.
In the table below, H does not represent hydrogen. Some elements are given in their own symbol and position in the periodic table while others are shown with a letter.
1A
1IIA
2IIIA
13IVA
14VA
15VIA
16VIIA
17O
18Li D O J Ne A Mg E Si H K B C F G L Answer the following questions.
Identify the most electronegative element.
Identify the most reactive element of group IA or 1.
Identify the element from period 3 with the smallest atomic size.
Identify the element with the highest ionization potential.
How many valence electrons are present in G ?
Which element from group 2 will have the least ionization energy ?
Identify the noble gas of the fourth period.
In the compound between A and H, what type of bond is formed ? Give its molecular formula.