Core Ideas of Chemistry

How many significant figures are present in 0.0025

• Two

• Three

• Four

• Five

How many atoms of magnesium are present in 96u of Magnesium

• 0.25

• 25

• 4

• 0.4

The volume of 1.7g of NH3 at STP (273K, 1atm) is

• 1.7L

• 2.24L

• 2.8L

• 3.4L

Number of moles present in 22.0g of carbondioxide is

• 2

• 22

• 0.5

• 0.25

If the density of a solution is 4.5g/mL, the mass of 1.4mL solution in significant figure is

• 3.21g

• 4.5g

• 0.63g

• 6.3g

The reactant which is entirely consumed when a reaction goes to completion is called

Which is more informative?

• Empirical Formula

• Molecular Formula

Mass percent of phosphorus in calcium phosphate is

• 38.71%

• 20%

• 41.29%

• 28%

................ refers to the agreement of a particular value to the true value of the result.

Law of definite proportions states that equal volumes of all gases under similar conditions of pressure and temperature contain equal number of molecules.

• True

• False