17. 25.3 g of sodium carbonate, Na, Co, is dissolved
in enough water to make 250 mL of solution. If
sodium carbonate dissociates completely, molar
concentration of sodium ion, Nat and carbonate
ions, coz-are respectively (Molar mass of
Na CO2 = 106 g mot') [AIPMT (Prelims)-2010]
(1) 0.955 M and 1.910 M
(2) 1.910 M and 0.955 M
(3) 1.90 M and 1.910 M
(4) 0.477 M and 0.477 M
Answers
Answered by
5
Answer:
Molar Mass of Na
2
CO
3
=106gmol
−1
Given Mass=25.3g
Volume=250mL
No. of moles of Na
2
CO
3
=
Molar Mass
Given Mass
=
106
25.3
=0.238 mole
Molarity=
Volume of Solution in L
No. of moles
=
250×10
−3
L
0.238
=0.954 M
Na
2
CO
3
⟶2Na
+
+CO
3
−2
1mole of Na
2
CO
3
gives 2mole of Na
+
and 1mole of CO
3
−2
0.952Mole⟶2×0.952moleofNa
+
=1.904M
⇒1×0.952moleofCO
3
−2
=0.952M
Na
+
=1.904M
CO
3
−2
=0.952M
Similar questions