arrange the following groups of elements in order of increasing ionization energy :
a. Be,Mg,Sr.
b. Bi,Cs,Ba.
c. Na,A1,S
To arrange the given groups of elements in order of increasing ionization energy, we need to understand what ionization energy is. Ionization energy is defined as the energy required to remove an electron from an atom or ion in the gaseous state.
The general trend of ionization energy across a period (horizontal row) in the periodic table is that it increases from left to right. This is because, as you move from left to right across a period, the atomic radius decreases and the effective nuclear charge increases, making it harder to remove an electron.
Now let's arrange the given groups of elements in order of increasing ionization energy:
a. Be, Mg, Sr:
- Beryllium (Be) is the first element in the group. It has the smallest atomic radius, so it requires the most energy to remove an electron. Therefore, it has the highest ionization energy.
- Magnesium (Mg) is the second element. It has a larger atomic radius compared to beryllium, so it requires less energy to remove an electron. Its ionization energy is lower than beryllium.
- Strontium (Sr) is the third element. It has the largest atomic radius among the three, so it requires the least energy to remove an electron. Its ionization energy is the lowest.
Therefore, the order of increasing ionization energy for group a is Sr < Mg < Be.
b. Bi, Cs, Ba:
- Bismuth (Bi) is the first element. It is located on the left side of the periodic table, indicating a larger atomic radius. Hence, it has the lowest ionization energy.
- Cesium (Cs) is the second element. It is located in the middle, so it has an intermediate atomic radius and ionization energy.
- Barium (Ba) is the last element. It is located on the right side of the periodic table, indicating a smaller atomic radius. Thus, it has the highest ionization energy.
Therefore, the order of increasing ionization energy for group b is Bi < Cs < Ba.
c. Na, Al, S:
- Sodium (Na) is the first element. It has a larger atomic radius, making it easier to remove an electron. Hence, it has the lowest ionization energy.
- Aluminum (Al) is the second element. It has a smaller atomic radius compared to sodium. Thus, it requires more energy to remove an electron, resulting in a higher ionization energy.
- Sulfur (S) is the last element. It has the smallest atomic radius, making it the most difficult to remove an electron. Therefore, it has the highest ionization energy.
Thus, the order of increasing ionization energy for group c is Na < Al < S.
a. Be, Mg, Sr:
To arrange the elements in order of increasing ionization energy, we need to consider the trend across a period of the periodic table, which generally increases from left to right.
Be (Beryllium) is the first element in the group, Mg (Magnesium) is in the middle, and Sr (Strontium) is at the end. Therefore, the correct order of increasing ionization energy is: Be < Mg < Sr.
b. Bi, Cs, Ba:
Again, we need to consider the trend across a period of the periodic table, which generally increases from left to right.
Bi (Bismuth) is the first element in the group, Cs (Cesium) is in the middle, and Ba (Barium) is at the end. Therefore, the correct order of increasing ionization energy is: Bi < Cs < Ba.
c. Na, Al, S:
This time, we need to consider the trend down a group or column of the periodic table, which generally decreases.
Na (Sodium) is the first element in the group, Al (Aluminum) is in the middle, and S (Sulfur) is at the end. Therefore, the correct order of increasing ionization energy is: S < Al < Na.