Answer to Question #174085 in General Chemistry for sarah

Question

calculate the molar concentration of sodium ions if 2.7g of sodium carbonate is dissolved in 175mL of water

Answer 1

Mass of sodium carbonate= 2.7g

Volume of water= 175ml= 0.175L

Mass conc of Na2CO3= 2.7g/0.175L= 15.43g/dm³

Molar mass of Na2CO3= 106g/mol

Molar concentration= mass concentration/molar mass= 15.43/106= 0.15mol/dm³

Now, it follows that Na2CO3 ionizes as follows

Na2CO3----> 2Na+ + CO3²-

Mopar concentration of Na+= 2(0.15)= 0.30mol/dm³