Unit 2 aim B
Practical 1: finding the accurate thermometer
Why did I calibrate the thermometers?
I calibrated the thermometer because I wanted to find out which thermometer was the most
suitable and accurate for me to use when I want to find the cooling rate for paraffin wax and
stearic acid for the two practicals. I produced a results table in which I took three repeats of
each thermometer, from then on by using my table of results and the average I decided I will
be using the thermometer that gave the readings closer to the temperature of boiling water
and ice, which in my case was the alcohol in glass thermometer.
Risk assessment
Hazard Risk Precaution
Glassware If the glass breaks, it can wear protective goggles,
pierce your skin and some gloves and lab coats
glass can fly into your eyes
Mercury in glass once mercury thermometer Move far away from the
thermometer breaks it quickly evaporates thermometer and let a
releasing vapours which can technician handle the
harm you if inhaled broken thermometer. Wear
protective gloves and
goggles as well as lab coats
Slip/trip/fall you can trip on bags,coats store bags and coats etc in
etc if they are on the floor cubby holes, tuck all chairs
and also chairs that haven’t under desks to clear the
been tucked under pathway
Bunsen burner It releases hot flames which Wear protective lab coats,
can burn your skin and hair goggles and don’t be too
close to the flames
Alcohol in glass It is fatal if swallowed and Wear protective gloves and
causes irritation to the skin goggles
and respiratory tract
Equipment
● Bunsen burner
● Crushed Ice
● 2 250 ml beakers
● Digital, mercury and alcohol thermometer
● Timer
● Distilled water
, Method for boiling water
Set up the clamp stand, Bunsen burner, clamp, gauze and tripod. Collect a 250cm3 beaker
and add 200cm3 of water and place this beaker on top of the gauze and tripod. Heat the
water until it starts bubbling and boiling. As soon as it starts boiling, place one of three
thermometers (digital, alcohol in glass and mercury in glass) in the beaker. Start the timer for
one minute and after one minute record the temperature in the table. Wait another one
minute and then after that minute start the timer again for another minute and take the next
temperature of repeat 2, then again wait another one minute before placing the
thermometers in the beaker for another minute and record the temperature of the 3rd repeat.
Make sure that the thermometers aren’t touching the sides of the beaker and the bottom of it
as well. Repeat this procedure for the remaining two thermometers. After you have your
repeats calculate your average
Method for ice
Collect a 250cm3 beaker and fill this with crushed ice, add some distilled water about the
width of your finger. Place one of three of the thermometers (digital, alcohol in glass and
mercury in glass) in the beaker making sure that it’s not touching the bottom or sides of the
beaker and wait one minute after one minute record the temperature in the table then wait
another minute and after that minute wait another minute to record the temperature for the
2nd repeat write down your results then wait another minute again and after that minute wait
another minute for the 3rd treat and record your result. Repeat this procedure with the other
two thermometers and calculate your average.
Results table
In my table of results, I produced 3 repeats for each type of thermometer used in boiling
water and ice and calculated the average so that I can increase the reliability of my results
and spot any anomalies. Using a digital thermometer gave me the least reliable results in
both boiling water and ice as it didn’t meet the actual temperature of boiling water and ice,
it’s also the least reliable as there were temperature fluctuations and the average wasn’t as
close to 100°C and 0°C compared to the other thermometers. So I knew that I wouldn't be
Practical 1: finding the accurate thermometer
Why did I calibrate the thermometers?
I calibrated the thermometer because I wanted to find out which thermometer was the most
suitable and accurate for me to use when I want to find the cooling rate for paraffin wax and
stearic acid for the two practicals. I produced a results table in which I took three repeats of
each thermometer, from then on by using my table of results and the average I decided I will
be using the thermometer that gave the readings closer to the temperature of boiling water
and ice, which in my case was the alcohol in glass thermometer.
Risk assessment
Hazard Risk Precaution
Glassware If the glass breaks, it can wear protective goggles,
pierce your skin and some gloves and lab coats
glass can fly into your eyes
Mercury in glass once mercury thermometer Move far away from the
thermometer breaks it quickly evaporates thermometer and let a
releasing vapours which can technician handle the
harm you if inhaled broken thermometer. Wear
protective gloves and
goggles as well as lab coats
Slip/trip/fall you can trip on bags,coats store bags and coats etc in
etc if they are on the floor cubby holes, tuck all chairs
and also chairs that haven’t under desks to clear the
been tucked under pathway
Bunsen burner It releases hot flames which Wear protective lab coats,
can burn your skin and hair goggles and don’t be too
close to the flames
Alcohol in glass It is fatal if swallowed and Wear protective gloves and
causes irritation to the skin goggles
and respiratory tract
Equipment
● Bunsen burner
● Crushed Ice
● 2 250 ml beakers
● Digital, mercury and alcohol thermometer
● Timer
● Distilled water
, Method for boiling water
Set up the clamp stand, Bunsen burner, clamp, gauze and tripod. Collect a 250cm3 beaker
and add 200cm3 of water and place this beaker on top of the gauze and tripod. Heat the
water until it starts bubbling and boiling. As soon as it starts boiling, place one of three
thermometers (digital, alcohol in glass and mercury in glass) in the beaker. Start the timer for
one minute and after one minute record the temperature in the table. Wait another one
minute and then after that minute start the timer again for another minute and take the next
temperature of repeat 2, then again wait another one minute before placing the
thermometers in the beaker for another minute and record the temperature of the 3rd repeat.
Make sure that the thermometers aren’t touching the sides of the beaker and the bottom of it
as well. Repeat this procedure for the remaining two thermometers. After you have your
repeats calculate your average
Method for ice
Collect a 250cm3 beaker and fill this with crushed ice, add some distilled water about the
width of your finger. Place one of three of the thermometers (digital, alcohol in glass and
mercury in glass) in the beaker making sure that it’s not touching the bottom or sides of the
beaker and wait one minute after one minute record the temperature in the table then wait
another minute and after that minute wait another minute to record the temperature for the
2nd repeat write down your results then wait another minute again and after that minute wait
another minute for the 3rd treat and record your result. Repeat this procedure with the other
two thermometers and calculate your average.
Results table
In my table of results, I produced 3 repeats for each type of thermometer used in boiling
water and ice and calculated the average so that I can increase the reliability of my results
and spot any anomalies. Using a digital thermometer gave me the least reliable results in
both boiling water and ice as it didn’t meet the actual temperature of boiling water and ice,
it’s also the least reliable as there were temperature fluctuations and the average wasn’t as
close to 100°C and 0°C compared to the other thermometers. So I knew that I wouldn't be
