Physical Chemistry MCQ with Answers

Physical Chemistry MCQ with Answers

81) Which of the following statements is not true about NaCl structure?

Answer is:

Na⁺ ions have coordination number 4

Explanation:

In NaCl crystal, Na⁺ ions have coordination number 6.

82) Most crystals show good cleavage because their atoms, ions or molecules are:

Answer is:

Arranged in planes

83) In a solid lattice, the cation has left a lattice site and is located at an interstitial position. The lattice defect is:

Answer is:

Frenkel defect

84) The ratio of cationic radius to anionic radius in an ionic crystal is greater than 0.732. Its coordination number is:

Answer is:

8

Explanation:

When radius ratio is between 0.732 and 1, then coordination number is 8 and structural arrangement is bcc.

85) Na and Mg crystallize in bcc and fcc type crystals respectively. The number of atoms of Na and Mg present in the unit cell of their respective crystal is:

Answer is:

2 and 4

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