+91-8076753736[email protected]
logo
logo
-->

Atoms And Molecules

Question
CBSEENSC9005098
Wired Faculty App

Calculate the molecular masses of H2, O2, Cl2, CO2, CH4, CH6, C2H4, NH3, CH3 OH.

Solution

Mass of hydrogen =1 u
Molecular mass of  H2 = 1+1 =2 u

Mass of oxygen=16u
Molecular mass of O2 = 16+16 = 32 u

Mass of Chlorine=35.5u
Molecular mass of Cl2 = 35.5 + 35.5 = 71 u

Mass of carbon =12u
Mass of oxygen=16u
Molecular mass of CO2 = 12 +32 = 44 u

Mass of carbon = 12u
Mass of hydrogen=1u
Molecular mass of C2H6 = 12 X 2 + 1 X6 = 30 u

Mass of carbon = 12u
Mass of hydrogen=1u
Molecular mass of C2H4 = 12 X 2 + 1 X 4 = 28 u

Mass of hydrogen=1u
Mass of carbon =12u
Molecular mass of NH3  = 1 X 14 + 1 X 3 = 17 u

Mass of carbon = 12u
Mass of hydrogen=1u
Mass of oxygen=16u
Molecular mass of CH3OH = 1 X 12 + 1 X 3 + 1 X 16 +1 X 1 = 32 u

Some More Questions From Atoms And Molecules Chapter

What is the mass of?

(a) 0.2 mole oxygen atoms.

(b) 0.5 mole of water molecules.

Calculate the number of molecules of sulphur (S8) present in 16 gm of solid sulphur.

Calculate the number of aluminium ions present in 0.56 gm of aluminium oxide.

Explain law of conservation of mass.

50 g of 10% lead nitrate is mixed with 50 g of 10% sodium chloride in a closed vessel. After the reaction has taken place, it was found that 6.83 g of lead chloride was precipitated. Besides, the reaction mixture contained 90 g water and sodium nitrate. Calculate the amount of sodium nitrate formed.

Name and explain two important laws of chemical combination ?

What are the postulates of Dalton’s atomic theory of matter?

Hydrogen and oxygen combine in two different ways to produce water and hydrogen peroxide. Which of Dalton’s law does this observation confirm? Explain.

State drawbacks of Dalton’s atomic theory of matter.

Mock Test Series

Mock Test Series

NCERT Sample Papers

Entrance Exams Preparation