Question

1. What is meant by the term "mole"? Calculate the number of moles in.
a.20 g of water ( atomic mass of H= 1 and O= 16)
b.2 g of Carbon dioxide ( atomic mass of C= 12 and 0 = 16)​

Answer 1

Answer:

Mole:

• The number equal to the number of carbon atoms is exactly 12 gram of pure 12C.
• Mole is the S.I unit.
• It is also called Avogadro's number.

1 mole = 6.022 * 10^23.

Step-by-step explanation:

Given:

• Given mass of Water (H2O) = 20g.

Atomic mass of:

• H = 1
• O = 16.

Molar mass of Water H2O = (1*2)+16g

Molar mass of H2O = 18g.

Number of moles = Given mass / Molar mass.

No. of moles = 20/18

No of moles = 1.111

Given:

• Given mass of Carbon dioxide (Co2)=2g.

Atomic mass of:

• C= 12g.
• O = 16g.

Molar mass of Co2 =( 12+16*2)g.

Molar mass of Co2 = 44g.

Number of moles = Given mass /molar mass.

No of moles = 2/44.

No of moles = 1/22.

Thank you ✔️.