Engineering Board Exam Reviewer · Chemistry · hard
A 25 mL sample of Na2CO3 solution requires 30 mL of 0.1 M HCl for complete neutralization ( Na2CO3 + 2 HCl 2 NaCl + H2O + CO2). What is the molarity of the Na2CO3 solution?
- 0.12 M
- 0.06 M
- 0.24 M
- 0.083 M
Answer
B. 0.06 M
Solution
n( HCl) = 0.1(0.030) = 0.003 mol n( Na2CO3) = 0.0015 mol. M = 0.0015/0.025 = 0.06 M.
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