wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

21.2 g of sodium carbonate (Na2CO3) is dissolved in enough water to make 250 mL of a solution. If it dissociates completely, the molar concentration of sodium ions (Na+) and the carbonate ions (CO23) are respectively:
(Molar mass of Na2CO3 = 106 g mol1)

A
0.8 M and 1.6 M
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
1.6 M and 0.8 M
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C
1.6 M and 1.6 M
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
0.8 M and 0.8 M
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is B 1.6 M and 0.8 M
Number of moles of Na2CO3=given mass (g)molar mass (g/mol)=21.2106=0.2 mol

Molarity=moles of Na2CO3Total volume of solution in mL×1000Molarity=0.2250×1000=0.8 M

According to the reaction: Na2CO32Na++CO23
1 M Na2CO3 will dissociate into 2 M of Na+ and 1 M of CO23
0.8 M of Na2CO3 dissociates into 2×0.8 M Na+=1.6 M Na+
0.8 M Na2CO3 dissociates to 0.8 M of CO23 .

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Reactions in Solutions
CHEMISTRY
Watch in App
Join BYJU'S Learning Program
CrossIcon