(b) The table gives the temperatures of the solutions before the student mixes them. potassium hydroxide solution 17.8 °C dilute hydrochloric acid18.4 °CCalculate the mean (average) temperature of the two solutions. (2) mean temperature = .............................................................. °C(c) The student repeats the experiment on a different day, using 25 cm 3of potassium hydroxide solution and 25 cm 3of dilute hydrochloric acid.The thermometer shows the highest temperature reached at the end of the experiment. °C 25 20(i) Complete the table by giving the missing information.Give both temperatures to the nearest 0.1 °C. (2) mean temperature at start in °C temperature at end in °C temperature rise in °C5.2
Question
(b) The table gives the temperatures of the solutions before the student mixes them. potassium hydroxide solution 17.8 °C dilute hydrochloric acid18.4 °CCalculate the mean (average) temperature of the two solutions. (2) mean temperature = .............................................................. °C(c) The student repeats the experiment on a different day, using 25 cm 3of potassium hydroxide solution and 25 cm 3of dilute hydrochloric acid.The thermometer shows the highest temperature reached at the end of the experiment. °C 25 20(i) Complete the table by giving the missing information.Give both temperatures to the nearest 0.1 °C. (2) mean temperature at start in °C temperature at end in °C temperature rise in °C5.2
Solution
To calculate the mean (average) temperature of the two solutions, you add the two temperatures together and then divide by the number of temperatures.
Step 1: Add the two temperatures together. 17.8°C (potassium hydroxide solution) + 18.4°C (dilute hydrochloric acid) = 36.2°C
Step 2: Divide the total by the number of temperatures. 36.2°C ÷ 2 = 18.1°C
So, the mean temperature of the two solutions is 18.1°C.
For the second part of the question, the mean temperature at the start is given as 5.2°C. The temperature rise is the difference between the temperature at the end and the temperature at the start.
If the temperature at the end is 20°C, then the temperature rise is:
20°C (temperature at end) - 5.2°C (temperature at start) = 14.8°C
If the temperature at the end is 25°C, then the temperature rise is:
25°C (temperature at end) - 5.2°C (temperature at start) = 19.8°C
So, the missing information in the table is:
mean temperature at start in °C: 5.2°C temperature at end in °C: 20°C or 25°C temperature rise in °C: 14.8°C or 19.8°C
Similar Questions
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