【Daily Question】September 14, 2016 – Participation +2 Wealth； +3 to 10 wealth for correct answers
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To increase the popularity of the chemical analysis section, a \"One Question per Day\" campaign has been launched to foster an active atmosphere for technical exchanges while offering members certain financial rewards. 【Daily Question】 (Single-choice question) To prepare 1000 mL of 0.1 mol/L HCl solution, how many milliliters of concentrated hydrochloric acid (12 mol/L HCl) are required? 1 A. 0.84 mL ； B, 8.4mL ； C, 1.2mL ； D, 12mL ； Standard answer: B. Reply with your answer in the post; you will receive +2 wealth points for participating in the quiz. An additional +3 to +8 wealth points will be given if you answer all questions correctly. Extra wealth rewards will be awarded if you provide a thorough analysis and explanation of the questions or answers, or if you include detailed calculation processes. If your answer is correct and your analysis and explanation are accurate, it will be marked as the best reply (or the best assistance). Feel free to answer the questions.
b, specifically 8.333 mL
When adding chemicals or cleaning equipment on a daily basis, we often need to convert concentrated solutions into dilute ones. The key point to keep in mind is that no matter how the concentration of the solution changes, the amount of solute dissolved in it remains constant. That is, C1V1 = C0V0, where C1 is the desired concentration of the dilute solution, V1 is the volume required to prepare the dilute solution, C0 is the concentration of the concentrated solution, and V0 is the volume required of the concentrated solution. According to the formula, the volume of the concentrated solution required is V0 = C1V1/C0 = 0.1 mol/L * 1000 ml / 12 mol/L = 8.333 ml.
1000*0.1 divided by 12, the result
According to the method for preparing titrants in the Chinese Pharmacopoeia: 9 ml → 1000 ml, 8.4 ml