Question

Name two soft metals which can be cut with a knife.


NCERT Class VIII
Science - Exemplar Problems

Chapter 4. Materials: Metals and Non-Metals

Answer 1

Sodium and Poatssium metals are the two metals which are soft and can be cut with a knife.
Reason:
-->Sodium and Potassium belongs to Alkali metals [first group of periodic table]
-->They are reactive metals.
-->As the atomic size increases down the group, hence the force of attraction between the valence electron and nucleus decreases. 
-->Metallic bonds are not strong .
-->Hence they are soft.
-->Potassium is more softer than sodium.

Answer 2

Sodium and Potassium are the two metals which can be cut with a knife.