Question

Help it’s urgent pls

Answer 1

Answer:

a) A molecular chemical formula employs symbols to denote the molecule of an element or of a compound. The rule for writing chemical formula is as follow:

Firstly, write the symbols with positive charge valency first. Secondly, write the valency of each atom on the top of its symbol. Thirdly, divide the valency number by their highest common factor ignore the positive or negative radicle. Interchange the valency of the radicle. Lastly, write the interchanged valency number to the lower right of the radicle.

b) 1)The presence of hair or fur.

2) Sweat glands.

3) Glands specialized to produce milk, known as mammary glands.

4) Three middle ear bones.

5) A neocortex region in the brain, which specializes in seeing and hearing.

6) Specialized teeth.

7) A four-chambered heart.