Answer:
The second column on the periodic table of the chemical elements is collectively called the alkaline earth metal group: beryllium, magnesium, calcium, strontium, barium, and radium. Because the outer electron structure in all of these elements is similar, they all have somewhat similar chemical and physical properties.
Explanation:
1s^2
2s^2
2p^6
3s^2
3p^6
4s^2
3d^10
4p^4
Remember that a cation will be smaller than its neutral atom, and an anion will be larger than its neutral atom. This would automatically eliminate answer choices A and D.
Also keep in mind that atomic radii decreases from left to right as you move along a periodic table. It also decreases from bottom up.
Atomic radii increases as you move from right to left and as you go from up to down.
As bromine is higher up in the periodic table than Iodine, it would have a smaller radius. Iodine would have a larger radius.
The correct answer is B. Br
The hybrid orbital of this molecule is 
. Hence, option C is correct.
<h3>What is hybridisation?</h3>
Hybridization is defined as the concept of mixing two atomic orbitals to give rise to a new type of hybridized orbitals.
In this compound, a hybrid orbital makes I-O bonds. Due to hybridization iodate should have tetrahedral geometry but because of the presence of lone pair of electrons the shape of 
the ion is pyramidal.
The hybrid orbital of this molecule is . Hence, option C is correct.
Learn more about hybridisation here:
brainly.com/question/23038117
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Answer:
DUPLET RULE: The tendency of an atom to acquire an outer most shell of two electrons is called duplet rule. OCTET RULE: The tendency of an atom to acquire an outermost shell of eight electrons is called the octet rule.
