Do Q 9

The elements Be, Mg and Ca each having two electrons in their outermost shells are in periods 2, 3 and 4 respectively of the modern periodic table. Answer the following questions, giving justification in each case :

(i) Write the group to which these elements belong.

(ii) Name the least reactive element.

(iii) Name the element having largest atomic radius .

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Solution

Dear Student,
1. These elements belong to alkali earth metals with group no.2
2. ca is a least reactive element
3. ca is largest in atomic radius
Regards

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Similar questions

Given below are some elements of the modern periodic table:

_{$4^{B e}, 9^{F e}, 14^{S i}, 19^{K}, 20^{C a}$}

(i)Select the element that has one electron in the outermost shell and write its electronic configuration.

(ii)Select two elements that belong to the same group. Give reason for you answer.

(iii) Select two elements that belong to the same period. Which one of the two has bigger atomic size?

Q. (a) What were the two major shortcomings of Mendeleev's periodic table? How have these been removed in the modern periodic table?
(b) Two elements X and Y have atomic numbers 12 and 16 respectively. Write the electronic configuration for these elements. To which period of the modern periodic table do these two elements belong? What type of bond will be formed between them and why?
(c) To which groups of the modern periodic table do the elements X and Y belong? Give reason for your answer.
(d) What could the elements X and Y be? Write their names and symbols.

Question 33
Three elements A, B and C have 3, 4 and 2 electrons respectively in their outermost shell. Give the group number to which they belong in the Modern Periodic Table. Also, give their valencies.

Q. Na, Mg and Al are the elements having one, two and three valence electrons respectively. Which of these elements (i) has the largest atomic radius, (ii) is least reactive? Justify your answer stating reason for each.

Q. Na, Mg and Al are the elements of the 3rd period of the Modern Periodic Table having group number 1, 2 and 13 respectively. Which one of these elements has the (a) highest valency, (b) largest atomic radius, and (c) maximum chemical reactivity ? justify your answer stating the reason for each.

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Dear Student, 1. These elements belong to alkali earth metals with group no.2 2.​ ca is a least reactive element 3. ca is largest in atomic radius Regards

Dear Student,
1. These elements belong to alkali earth metals with group no.2
2. ca is a least reactive element
3. ca is largest in atomic radius
Regards