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

Question

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

Asked by Vishal kumar | 1 year ago | 337

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Class 9 Science Atoms and Molecules Add Answer

Calculate the number of aluminium ions present in 0.051g of aluminium oxide.

(Hint: The mass of an ion is the same as that of an atom of the same element. Atomic mass of Al = 27u)

Class 9 Science Atoms and Molecules View Answer

What is the mass of:

(a) 0.2 mole of oxygen atoms?

(b) 0.5 mole of water molecules?

Class 9 Science Atoms and Molecules View Answer

Convert into mole.

(a) 12g of oxygen gas

(b) 20g of water

(c) 22g of carbon dioxide

Class 9 Science Atoms and Molecules View Answer

What is the mass of -

(a) 1 mole of nitrogen atoms?

(b) 4 moles of aluminium atoms((Atomic mass of aluminium =27)?

(c) 10 moles of sodium sulphite (Na₂SO₃)?

Class 9 Science Atoms and Molecules View Answer

Calculate the molar mass of the following substances.

(a) Ethyne, C₂H₂

(b) Sulphur molecule, S₈

(c) Phosphorus molecule, P4 (Atomic mass of phosphorus =31)

(d) Hydrochloric acid, HCl

(e) Nitric acid, HNO₃

Class 9 Science Atoms and Molecules View Answer

Accepted Answer

To calculate molecular mass of sulphur:

Molecular mass of Sulphur (S8) = 8xMass of Sulphur = 8x32 = 256g

Mass given = 16g

Number of moles = mass given/ molar mass of sulphur

= 16/256 = 0.0625 moles

To calculate the number of molecules of sulphur in 16g of solid sulphur:

Number of molecules = Number of moles x Avogadro number

= 0.0625 x 6.022 x 10²³ molecules

= 3.763 x 10²² molecules

Answered by Shivani Kumari | 1 year ago