Question

Which of the following metal can be cut with the knife?
A. Gold
B. Potassium
C. Iron
D. None of the above

Answer 1

Hint: We know that metals with low melting point, less density and soft in nature can be easily cut by knife. Metals with high melting point, high density and hardness are difficult to cut with the knife. Hard metals can be cut using proper machines.

Complete step by step answer:
As we know that to cut metal with a knife , the metal should be soft enough. Earth metals or the first group metals are soft metals. They have low density as compared to other metals of the entire periodic table. So they can be easily cut by a knife. Some of the soft earth metals are Lithium, Potassium and Sodium. Metals like Gold and Iron are hard and dense . They are malleable and ductile. They are very tough and it's nearly impossible to be cut with a knife. Proper machines and techniques are used to cut such metals.
So from the above explanation it is clear to us that earth metals like lithium .sodium and potassium can be cut with a knife.

So the correct answer to the question is option : B. Potassium.

Additional information:
 Potassium is a shiny metal. It has a low density. In flame test, Potassium gives bright red flame. It was the first metal to be discovered by electrolysis. Many fruits are also rich in potassium minerals. Some of the examples are bananas, spinach, potatoes , peas, cucumber and many more.

Note:
Always remember that Potassium has an atomic number of $19$ . It is a soft metal because it has low density and low ,melting point as compared to other metals. Potassium belongs to the first group of the periodic table that is the S Block.