Relative atomic and molecular mass. Balan

Q1. The relative atomic mass is the average mass of an atom compared to

• 1/12 the mass of a carbon atom.

• 1/12 the mass of a carbon-12 atom

• 12 times the mass of a carbon -12 atom

• 12 times the mass of a carbon atom

Carbon atom is chosen as element for the relative atomic mass because it

• exist in large quantity in earth crust

• reacts easily with all metals only

• can be handled easily

• has high melting and boiling point

3. Relative atomic mass of an atom is the

• nucleon number of the atom

• proton number of the atom

• number of neutron of the atom

• number of electron of the atom.

How many nitrogen atoms makes up the same relative atomic mass as 1 iron atom? (R.a.m ; N=14, Fe=56)

• 1/4

• 4

• 42

• 70

Relative atomic mass of Bromine is equal to...

(R.am.; O=16, N=14, Mg=24, Fe=56, Br=80)

• 5 nitrogen atoms

• 6 oxygen atoms

• the sum of 1 magnesium and 1 iron atoms

• the sum of 2 oxygen and 3 nitrogen atoms

What is the relative formula mass of Pb(NO₃)₂.

(R.am.; O=16, N=14, Pb=207)

• 269

• 317

• 331

• 538

Calculate the relative molecular mass of P₂O_5.

(R.am.; O=16, P=31)

Calculate the relative molecular mass of CCl_4.

(R.am.; C=12, Cl=35.5)

Calculate the relative formula mass of K₃Fe(CN)₆.

(R.am.; C=12, N=14, K=39, Fe=56)

Calculate the relative formula mass of K₃Fe(CN)₆.

(R.am.; C=12, N=14, K=39, Fe=56)