The diagram shows apparatus that can be used to measure the melting point of a
solid Q.. The solid Q is placed in a small tube. The small tube is then put into a liquid
contained in a beaker. The liquid is gently heated and temperature at which solid Q
melts is recorded.
a. Give the name of the apparatus labeled ‘ P ‘. What is the SI unit of temperature?
b. Solid Q melts at 140 0 C. Explain why water is not a suitable liquid to use in this
experiment.
c. Suggest why the liquid in the beaker needs to be stirred constantly.
Answers
Answer:
a) the apparatus 'P' is most likely to be a thermometer.
the SI unit of temperature is Kelvin denoted by K.
b) Water is not a suitable liquid for it because water starts to boil and turn into vapour at 100°C .
c) The liquid in the beaker needs to be stirred constantly as it will help in heating of water fact .
Explanation:
for b) based on fact that solid melts at 140°C and boiling point of water is 100°C . If you remember the lesson in chemistry about matter you will know that once water reaches its boiling point its temperature stops increasing and it remains at its boiling point.
for c) reason is if you stir the liquid it will help in convection . Thus molecules will get more kinetic energy and will move faster thus the liquid will get hotter.
Hope it helps you friend...