Question

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Kindly answer the first question

Answer 1

Answer:

The elements with atomic numbers 7, 8 and 9 are nitrogen, oxygen and fluorine respectively. The atomic size decreases from left to right in the modern periodic table. Hence, the decreasing order of their atomic radii is N>O>F.

Atomic number is defined as the sum of total number of protons present in an atom. Each element has different atomic number.

Atomic radius of the elements across the period in a periodic table decreases from left to right due to the addition of electrons into the same shell. Whereas atomic radius increases from top to bottom in a group.

An element with atomic number 7 is nitrogen. Element with atomic number 8 is oxygen and it belongs to group 16.

Element with atomic number 9 is fluorine and it belongs to group 17.

(a)   Element X, belongs to group 15 and period 2 in the modern periodic table.

Element Y, belongs to group 16 and period 2 in the modern periodic table.

Element Z, belongs to group 17 and period 2 in the modern periodic table.

(b)  The atomic radius of X, Y, and Z elements in decreasing order of their atomic radii are as follows.

                        Nitrogen > Oxygen > Fluorine

or,                           X > Y > Z

(c)  Though nitrogen and fluorine combine together to result in the formation of number of compounds. But one compound when both nitrogen and fluorine chemically combine together is  NF_{3} or XZ_{3}

Explanation:

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