Question
Question: Which of the following metals gives silver white colour? (A) Nickel (B) Sodium (C) Lead (D) ...
Which of the following metals gives silver white colour?
(A) Nickel
(B) Sodium
(C) Lead
(D) Antimony
Solution
Flame test is a very important test used in quality analysis of a compound. A cation is identified by this test because different cations give different colours in this test. This element is found in the 4th period which gives silver White colour.
Complete step by step answer
Normally, the presence of a metal ion or cation can be detected by the flame test. Flame test is based on the concept that when an element is given energy, its electrons get excited and absorb a certain amount of wavelength and then when they come to the ground state they emit several spectrums of lights.
Now, by studying the properties of each of the metal given:
Nickel: nickel has an atomic number 28. Nickel consists of all the properties that a metal has, it is lustrous, ductile and hard and it belongs to the transition metal. It is considered to be found in a silvery white state and gives white colour to the flame test.
Sodium: sodium has atomic number 11.It is a soft matter. Now sodium, when introduced to the flame test, is believed to give an intense yellow colour flame.
Lead: lead is considered to have an atomic number 82. It can be cut by a knife, though it is a heavy metal. It is malleable. Now when you introduce the flame test, it is believed to give a white flame.
Antimony: Antimony is considered to have an atomic number 51. The result of the flame test of an antimony atom is pale green.
Correct option is A.
Note
Always remember that the colour of a metal and the colour, which it gives on the flame test is because of a totally different concept. One is possessed by it naturally, and the other is because of the excitation of its electron.