Question

.The description of atomic particles of two elements X and Y is given below: [3]

X Y

Protons

Neutrons

Electrons 8

8

8 8

9

8

(a) What is the atomic number of Y?

(b) What is the mass number of X?

(c) What is the relation between X and Y?

(d) Which element/elements do they represent?

(e) Write the electronic configuration of X.

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Answer 1

Question:

(i) What is the atomic number of Y?

(ii) What is the mass number of X?

(iii) What is the relation between X and Y?

(iv) Which element/elements do they represent?

(v) Write the electronic configuration of X?

(vi) Write the cation/anion formed by the element.

Answer:

(i) Atomic number of Y = no. of electrons/protons = 8

(ii) Mass number of X = no. of protons + no. of neutrons = 8 + 8 =16

(iii) X and Y are isotopes since they have same atomic number.

(iv) X and Y represent Oxygen since oxygen has Atomic number = 8.

(v) Electronic configuration: 2, 6.

(vi) It will form an anion: O-2

Answer 2

(i) Atomic number of Y = no. of electrons/protons = 8

(ii) Mass number of X = no. of protons + no. of neutrons = 8 + 8 =16

(iii) X and Y are isotopes since they have same atomic number.

(iv) X and Y represent Oxygen since oxygen has Atomic number = 8.

(v) Electronic configuration: 2, 6.

(vi) It will form an anion: O-2