S3-Q5- Mole concept and titration

The mole

• is the quantity of matter That contains Avogadro's number of particles

• is the sum of atomic masses of the molecules expressed in gm

• always contains equal number of atoms and ions

• Occupies a volume of 22.4 L at STP of any matter whatever its physical state

Numbers of atoms in 2 moles of sodium hydroxide is equal to -------

• 6.02x10²³

• 2x 6.02x10²³

• 6x6.02x10²³

• 3x6.02x10²³

If we have 2 moles of water then which of the following is correct [H=1; O=16]

• The total mass is 18 gm

• the total volume is 44.8 Liters at STP

• The total number of molecules is 12.04x10²³ molecules

• The total number of atoms is 12.04x6.02x10²³ atoms

what is the mass of calcium sulphate CaSO4 , that should be added to 200 ml of water to prepare 2 molar solution ?

• 54.4gm

• 54400gm

• 35.2gm

• 27.2gm

If you know that the atomic mass of the Phosphorus P=31 u , then the molar mass of the phosphorus in the vapour state is --------

• 31 u

• 31g/mol

• 124 u

• 124 g/mol

1 mole of lime water contains all the following except ------------

• 6.02x10²³ molecules

• 1.204x10²⁴ hydroxide radicals

• 12.04x10²³ ions of oxygen

• 12.04x10²³ atoms of oxygen

The mass of 0.1 mol of sodium hydroxide is equal to --------

[Na=23; O=16; H=1]

• 0.04g

• 0.4g

• 4g

• 40g

a mole of sodium aluminate contains -------

• 2 mol Na

• 2 mol Al

• 2 mol O

• 4 mol O

The molar mass of the barium sulphite is --------- [Ba=137 ; S=32 ; O=16]

• 233 g/mol

• 217 g/mol

• 354 g/mol

• 514 g/mol

The number of the molecules of oxygen in 466.6 ml sample of oxygen gas at STP is ---------- molecules

• 1.25x10²²

• 1.34x10²²

• 6.02X 10²²

• 3x10²⁶