English Medium कक्षा ९ - CBSE Question Bank Solutions

Which of the following are physical changes ?

1. melting of iron metal
2. rusting of iron metal
3. bending of an iron rod
4. drawing a wire of iron metal

Which of the following are chemical changes ?

1. decaying of wood
2. burning of wood
3. sawing of wood
4. hammering of nail into wood

Lysosomes are also called digestive bags. Why?

One of the following elements has an atomicity of ‘one’. This element is :

If the aluminium salt of an anion X is Al2X3, what is the valency of X ? What will be the formula of the magnesium salt of X ?

What is a group of 6.022 × 10²³ particles known as ?

What name is given to the amount of substance containing 6.022 × 10²³ particles(atoms,molecules or ions) of a substance ?

How many atoms are present in one gram atomic mass of a substance ?

How many moles are 3.6 g of water ?

What is the mass of 0.2 mole of oxygen atoms ?

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A mole represents an .............. number of particles of a substance.

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60 g of carbon element are .............. moles of carbon atoms.

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0.5 mole of calcium element has a mass of ............... .

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64 g of oxygen gas contains ................ moles of oxygen atoms.

What name is given to the amount of substance containing this number of atoms ?

How many moles of calcium carbonate (CaCO₃) are present in 10 g of the substance ? (Ca = 40 u ; C = 12 u ; O = 16 u)

How many moles of O2 are there in 1.20 × 1022 oxygen molecules ?

How many moles are there in 34.5 g of sodium ? (Atomic mass of Na = 23 u)

If 16 g of oxygen contains 1 mole of oxygen atoms, calculate the mass of one atom of oxygen.

How many atoms are there in 0.25 mole of hydrogen ?