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Atoms & Molecules

Compute the number of ions present in 5.85 g of sodium chloride.

05/11/2024

Science

9th

Atoms & Molecules

Raunak took 5 moles of carbon atoms in a container and Krish also took 5
moles of sodium atoms in another container of same weight. (a) Whose
container is heavier? (b) Whose container has more number of atoms?

05/11/2024

Science

9th

Atoms & Molecules

The difference in the mass of 100 moles each of sodium atoms and sodium
ions is 5.48002 g. Compute the mass of an electron.

05/11/2024

Science

9th

Atoms & Molecules

You are provided with a fine white coloured powder which is either sugar or salt. How would you identify it without tasting?

05/11/2024

Science

9th

Atoms & Molecules

Does the solubility of a substance change with temperature? Explain with the help of an example.

05/11/2024

Science

9th

Atoms & Molecules

What is the fraction of the mass of water due to neutrons?

05/11/2024

Science

9th

Atoms & Molecules

Give the chemical formulae for the following compounds and compute the
ratio by mass of the combining elements in each one of them. (You may
use appendix-III).
(a) Ammonia
(b) Carbon monoxide
(c) Hydrogen chloride
(d) Aluminium fluoride
(e) Magnesium sulphide

05/11/2024

Science

9th

Atoms & Molecules

Which of the following symbols of elements are incorrect? Give their correct
symbols
(a) Cobalt CO
(b) Carbon c
(c) Aluminium AL
(d) Helium He
(e) Sodium So

05/11/2024

Science

9th

Atoms & Molecules

Give the formulae of the compounds formed from the following sets of
elements
(a) Calcium and fluorine
(b) Hydrogen and sulphur
(c) Nitrogen and hydrogen
(d) Carbon and chlorine
(e) Sodium and oxygen
(f) Carbon and oxygen

05/11/2024

Science

9th

Atoms & Molecules

Write the molecular formulae for the following compounds
(a) Copper (II) bromide
(b) Aluminium (III) nitrate
(c) Calcium (II) phosphate
(d) Iron (III) sulphide
(e) Mercury (II) chloride
(f) Magnesium (II) acetate

05/11/2024

Science

9th