【Daily Question】August 12, 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) If Na2B4O7•10H2O, which is stored in a regular desiccator, is used as a reference substance to determine the concentration of hydrochloric acid, then the concentration of hydrochloric acid will ( ) A. Be too high B. Be too low C. Be unaffected D. It cannot be determined. Correct answer: B. Reply with your answer; participating in the quiz earns you +2 wealth points. Those who get all answers correct will receive an additional +3 to +8 wealth points. Those who provide a thorough analysis or explanation of the question and answers, or include detailed calculation processes, will receive extra wealth points as a reward. If your answer is correct and your analysis is accurate, it will be marked as the best reply (or best assistance). Feel free to answer the questions.
B、Low 【The water in Na2B4O7•10H2O increases the solubility in hydrochloric acid solution, thereby reducing the concentration of hydrochloric acid】
B :) If sodium borate decahydrate is not stored properly, it can lose its crystalline water, resulting in a higher concentration of the standard solution prepared. As a consequence, less of this standard solution is required when titrating the hydrochloric acid standard solution, which leads to lower calculated values; in other words, the concentration of the hydrochloric acid solution turns out to be lower than expected.
Choose B; the dryer causes the loss of crystalline water, which leads to increased consumption of hydrochloric acid and a lower concentration.
If Na2B4O7•10H2O, which is stored in a regular desiccator, is used as a reference substance for calibrating the concentration of hydrochloric acid, then the concentration of hydrochloric acid will be (B) A. too high B. too low C. unaffected D. indeterminable