GCSE Science Chemistry ISA Method Viscosity

Hypothesis

The viscosity of oil depends on its temperature.


Equipment

• Vegetable oil in a test tube
• Beaker
• Thermometer
• Pipette
• White tile
• Ruler 
• Clamp stand, boss and clamp
• Stopwatch
• Hot water/kettle

Method

Boil some water in a kettle and pour it into a beaker. Place the test tube of vegetable oil into the beaker and a thermometer into the test tube. Wait a few minutes until the oil has reached the same temperature as the hot water. Angle a white tile so it's sloping downwards and is held securely by a clamp stand. Using the ruler mark a line 5 cm long going straight down the tile. Take the pipette and fill it with oil, releasing it on the top of the line on the tile. Using the stopwatch, time how long it takes for the oil to flow down the tile and travel 5 cm. Record this time. Let the oil in the test tube cool slightly and repeat for a range of temperatures.

Variables

Independent - temperature of oil

Dependent - time taken to flow down tile (the more viscous the oil, the longer this will take)

Control - Angle of tile, volume of oil, distance oil flows (5cm)

Risk assessment

This is a very safe experiment but care must be taken handling the hot water from the kettle. The risk is low but goggles should be worn when pouring hot water.

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Physics in video games

If you feel like taking a break from all your ISA preparation, try watching the youtube video below. It explains how Physics, similar to what you study in school is used in video games and gaming.

And this is a demo of the Physics engine that is used in GTA 4:

GCSE Science Physics ISA method Water Cooling controlled assessment

Hypothesis

The temperature decrease of hot water in a container, after a fixed period of time, depends upon the starting temperature of the water


Equipment

• Beaker 
• Thermometer
• Electric Kettle
• Stopwatch

Method

Pour hot water from the kettle into the beaker and record the starting temperature. Leave the beaker for 5 minutes and record the temperature it has cooled to. Repeat the experiment with 5 other starting temperature of water.

Variables

Independent - starting temperature of water

Dependent - final temperature of water

Control - volume of water, size and shape of beaker, room temperature

Risk Assessment

This is a low risk assessment but you must take care handling hot water from the kettle to avoid burns and scalds.

GCSE Chemistry ISA Controlled Assessment Ions that cause Hard Water

Hypothesis

Group 2 metal ions cause hardness in water

Equipment

• 6 samples of water each containing different metal ions
• Soap solution
• Conical flask (small)
• Pipette
• Measuring cylinder

Method

Take the first sample and pour 10 centimetres cubed of it into the conical flask. Add 1 cm cubed of soap solution using the pipette, put a stopper in the top of the conical flask and shake the flask for 10 seconds. Observe the lather that's formed on the top of the water - if it lasts for longer than 1 minute then we can consider it to be a permanent lather and we can record that. If the lather fades away after less than a minute add another centimetre cubed and repeat. Keep doing this until the lather does persist for at least a minute. Record how much soap solution was required to produce a permanent lather with that metal ion present and repeat the whole process for the remaining metal ions.

Variables

Independent variable - type of metal ion

Dependent variable - Volume of soap solution required to produce a permanent lather

Control variable - Amount of shaking, type of soap solution used, type of flask used

Risk Assessment

This is a very safe experiment (i.e. low risk). Care must be taken with spillages and they must be wiped up immediately.

GCSE Biology ISA Lungs

Hypothesis

The taller a person is the larger the maximum volume of air that the person can breathe out of that person's lungs is.


Equipment

• Large, callibrated (with a scale marked on) container
• Wide plastic tube
• Sterilised mouthpiece (with supply of sterilising solution e.g. Milton)
• Large bowl of water
• Metre rules

Method

Fill the large container with water and turn upside down so that the opening is under water in the large bowl. Thread one end of the plastic tubing into the large container. Either attach the sterilised mouthpiece to the other end of the tubing or sterilise the end of the tubing directly. Record the height of the first volunteer using the metre rules to measure this. Get your first volunteer to pinch their nose and breathe in and out deeply several times. Now, get them to take a deep breath in  and exhale deeply into the tube/mouthpiece. Using the scale on the side of the container, record how much air has been breathed out into it. Repeat these steps for another 5 volunteers.

Variables

Independent - Height of person

Dependent - Volume of air breathed out

Control - Diameter of tube, temperature of air, position of person (seated/standing), pulse rate of person

Risk Assessment

The risks in this experiment are low but care must be taken to ensure the mouthpieces and tube are properly sterilised between uses. This will prevent any infection/germs being spread from one person to the next.

For a bit of extra background reading try https://en.wikipedia.org/wiki/Lung_volumes