fundaemental

Question 1

relative atomic mass

Answer 1

mass of one atom of an element compared with mass of one atom of carbon taken as 12.

Question 2

unit of atomic mass

Answer 2

a.m.u.
the mass of 1/12th of an atom of carbon 12 is called atomic mass unit.

1a.m.u= 1.661x10-27 kg

Question 3

determination of empirical formula (4 steps)

Answer 3

1. percentage composition
   % of element=mass of element in a compound/mass of compound x100

2.no.of moles=mass/atomic mass

3. atomic ratio

4, whole number atomic ratio

Question 4

For which structures is empirical formula used

Answer 4

used for ionic compounds and giant covalent structures. SiO2, diamond graphite etc. also glucose, fructose , formaldehyde wegaira

Question 5

main diff between molecular and empirical formula.

2) relation bw both.

Answer 5

EF used for both molecular and ionic compounds. MF use only for molecular compounds.

MF= n x EF

Question 6

limiting reactant definition and identification.

Answer 6

reactant that produces least no. of moles of product and is consumed earlier in the reaction.

3 steps for id.
1. calculate “n” from given amount of reactants
2. calculate “n” of product from given moles of each reactant.
3. identify the reactant as limiting which produces least amount of moles of product.

Question 7

YIELD AND TYPES OF YIELD.

Answer 7

amount of product obtained as a result of chemical reaction is yield.

1. Theoretical yield: amount of product calculated from the balanced chemical equation.
2. Actual yield: amount of product obtained experimentally
3. Percentage yield:
   % yield= actual/theoretical x 100