LEEN was observing the physical properties of elements in order to classify them as either a metal, non-metal, metalloid or any other type of element. The first element was dull, brittle, and did not conduct heat. What would its classification be Metal

Non-metal

Metalloid

Radioactive element

Non-metal

Explanation:

A non-metal is a substance that possesses the following characteristics:

- It is brittle i.e can break easily

- It does not conduct heat and electricity

- It is not lustrous i.e does not shine when polished.

According to this question, LEEN was observing the physical properties of elements in order to classify them. He found that the first element was dull, brittle, and did not conduct heat. This makes it a NON-METAL.

it's c. elements are placed in rows based on how may valencies electrons have.