酸碱滴定法测试氢氧化钙溶液PH值.doc

酸碱滴定法测试氢氧化钙溶液PH值1. 原理不同浓度的氢氧化钙溶液同定量的标准溶液进行滴定，发生中和反应，以无水乙醇酚酞液作指示剂，观察等当点，根据消耗的氢氧化钙溶液的毫升数，查表知该浓度对应的PH值。2. 试剂标准溶液配制X克/500ML标准溶液：用1/10000的天平称取X克，再用1/10的天平称取Y克分析纯氯化钠，一并加入到干净的500ML的容量瓶里，然后加入纯净水或蒸馏水至刻度，放置12小时并摇均匀。酚酞配制1克/100ML酚酞乙醇溶液：用1/10的天平称取1克酚酞，家人到125ML的滴瓶里，然后加入100ML乙醇，摇匀。3. 仪器及用具1 滴定架2 1/10天平3 1/10000天平4 250ML三角瓶5 25ML碱式滴定管2支6 500ML容量瓶7 125ML滴瓶4. 试样采取用干净的塑料杯取沉淀好的清澈氢氧化钙溶液5. 操作方法给1号滴定管加入25ML浓度为X克/500ML标准溶液；再给2号滴定管加入需测PH的氢氧化钙溶液，用被测氢氧化钙液洗涤滴定管3次，最后加至25ML。从1号滴定管给干净的三角瓶加入（？）ML标准液，再加入7滴酚酞指示剂，用被测氢氧化钙滴定至微红色，及到等当点，根据消耗被测液氢氧化钙的毫升数，查表知其PH值。 被测氢氧化钙消耗数与其PH对应关系表被测氢氧化钙消耗数ML氢氧化钙溶液PH值4.412.304.512.294.612.284.712.274.812.264.912.255.012.245.112.235.212.225.312.215.412.205.512.195.612.195.712.175.812.165.9-6.012.156.1-6.212.146.3-6.412.136.5-6.612.126.7012.116.8012.106.9012.097.0012.087.1012.077.2012.067.3012.057.4012.047.5012.037.60-7.7012.027.80-7.9012.018.00-8.1012.008.20-8.3011.998.40-8.5011.988.60-8.711.978.80-8.9011.969.00-9.1011.959.20-9.3011.949.40-9.5011.939.60-9.7011.929.80-9.9011.9110.10-10.2011.9010.30-10.5011.8910.60-10.8011.8810.90-11.0011.8711.10-11.3011.8611.40-11.6011.8511.70-11.9011.8412.2011.8312.4011.8212.6011.8112.8011.8013.0011.7913.2011.7813.4011.7714.0011.7614.1011.7514.2011.7414.4011.7314.7011.7215.2011.7115.7011.7016.2011.6916.6011.6816.8011.6717.2011.6518.0011.6318.6011.6119.2011.5919.7011.5620.3011.5321.0011.5021.1011.4721.2011.4521.7011.4222.3011.4023.0011.3823.1011.3523.2011.3224.1011.3024.2011.2824.3011.2524.4011.2324.5011.2024.6011.1924.7011.1724.8011.10注意事项：1.对浑浊的氢氧化钙溶液不能测试，配制液需要沉淀12小时以上方可测试。也就是说，先一天配制，第二天测试，取样液要及时测试，以防PH值下降。 2.滴定时要把滴定管里的空气排干净，滴定要缓慢进行，根据指示剂颜色变化，确定终点到来。 3.假设控制值为11.88，如果实际测值11.87或11.89需加适量的氢氧化钙或柠檬酸调PH值，加量参考以下表数据。 4.用9.18标定溶液和滴定获得的氢氧化钙溶液的PH来校准酸度计。具体调整定位旋扭和斜率旋扭使之与以对应。再用校准后的酸度计检测其他水溶液的PH值。获得的数据就非常准确。PH调高原液PH值加石灰/2水调后PH8.711130克11.889.671000克11.8810.22790克11.8810.71580克11.8810.92417克11.8810.93415克11.8810.94413克11.8810.95411克11.8810.96409克11.8810.97407克11.8810.98405克11.8810.99403克11.8811.00401克11.8811.01399克11.8811.02397克11.8811.03395克11.8811.04393克11.8811.05391克11.8811.06389克11.8811.07387克11.8811.08385克11.8811.09382克11.8811.10380克11.8811.11377克11.8811.12374克11.8811.13371克11.8811.14368克11.8811.15365克11.8811.16362克11.8811.17359克11.8811.18356克11.8811.19353克11.8811.20350克11.8811.21347克11.8811.22344克11.8811.23341克11.8811.24338克11.8811.25335克11.8811.26332克11.8811.27329克11.8811.28326克11.8811.29323克11.8811.30320克11.8811.31317克11.8811.32314克11.8811.33311克11.8811.34308克11.8811.35305克11.8811.36302克11.8811.37299克11.8811.38296克11.8811.39293克11.8811.40290克11.8811.41287克11.8811.42284克11.8811.43281克11.8811.44278克11.8811.45275克11.8811.46272克11.8811.47269克11.8811.48266克11.8811.49263克11.8811.50259克11.8811.51255克11.8811.52251克11.8811.53247克11.8811.54243克11.8811.55239克11.8811.56235克11.8811.57231克11.8811.58227克11.8811.59223克11.8811.60219克11.8811.61215克11.8811.62210克11.8811.63205克11.8811.64200克11.8811.65195克11.8811.66190克11.8811.67185克11.8811.68180克11.8811.69175克11.8811.70170克11.8811.71165克11.8811.72160克11.8811.73150克11.8811.74140克11.8811.75130克11.8811.76120克11.8811.77110克11.8811.78100克11.8811.7990克11.8811.8080克11.8811.8170克11.8811.8260克11.8811.8350克11.8811.8445克11.8811.8535克11.8811.8625克11.8811.8715克11.8811.882011.9011.881011.89 调低原液加柠檬酸/水12.22585克11.8812.21565克11.8812.20535克11.8812.19510克11.8812.18485克11.8812.17460克11.8812.16435克11.8812.15410克11.8812.14380克11.8812.13360克11.8812.12345克11.8812.11330克11.8812.10315克11.8812.09300克11.8812.08285克11.8812.07270克11.8812.06255克11.8812.05240克11.8812.04225克11.8812.03210克11.8812.02195克11.8812.01180克11.8812.00165克11.8811.99150克11.8811.98135克11.8811.97