Ever wondered how scientists study tiny cells or test what's... Show more
Essential Chemistry Practical Activities for Paper 1






Using a Microscope to Study Cells
Want to see the incredible world inside an onion? This practical shows you how to prepare a specimen and use a microscope properly. You'll need to carefully peel off a thin layer of epidermal tissue from an onion using tweezers.
The secret to getting a clear image is proper preparation. Place your tissue sample on a glass slide with a drop of water, then add iodine to stain the cells. This makes the cell structures much easier to spot under the microscope.
Using the microscope takes practice, but it's quite straightforward once you know the steps. Always start with the lowest-powered objective lens, use the coarse adjustment knob to get roughly in focus, then fine-tune with the fine adjustment knob. Remember to move the stage down gradually whilst looking through the eyepiece.
Top tip: Never force the adjustment knobs - gentle movements prevent damage to both the slide and the microscope lens!

Investigating Osmosis with Potato Cylinders
This osmosis experiment shows how water moves through cell membranes - something that's happening in your body right now! You'll cut identical potato cylinders using a cork borer and scalpel, then watch what happens when you place them in different concentrations of sugar solution.
The key to reliable results is making everything identical at the start. All cylinders must be the same diameter and length, and you'll need to measure their mass accurately. Each cylinder goes into a different boiling tube with various sugar concentrations, including pure distilled water as a control.
After leaving them for a set time, you'll measure the cylinders again. Some will have gained mass (water moved in), whilst others will have lost mass (water moved out). This demonstrates how osmosis works - water always moves from areas of low solute concentration to high solute concentration.
Remember: Blot the cylinders dry before final measurements to get accurate results!

Testing How pH Affects Enzyme Activity
Enzymes are biological catalysts that speed up reactions, but they're incredibly fussy about conditions! This practical uses amylase enzyme to break down starch into simpler sugars, and you'll discover how pH affects the reaction speed.
The clever part is using iodine as an indicator. When starch is present, iodine turns blue-black, but when the starch gets broken down into maltose, the iodine stays its normal colour. You'll test a drop of your reaction mixture every 10 seconds until the colour change stops happening.
Different pH levels dramatically affect enzyme performance. At pH 7 (neutral), amylase works efficiently and completes the reaction in about 60 seconds. However, at extreme pH values like pH 14, the enzyme becomes denatured and stops working entirely.
Key insight: Enzymes have an optimal pH range - step outside it and they lose their shape and function!

Food Tests - Detecting Nutrients
These four food tests help you identify what nutrients are lurking in different foods - it's like being a food detective! Each test uses a specific reagent that produces a distinctive colour change when the target nutrient is present.
Benedict's test for sugars involves heating your sample with Benedict's solution. A positive result shows a colour change from light blue to green, yellow, orange, or brick-red depending on sugar concentration. The iodine test for starch is simpler - just add a few drops and look for the characteristic blue-black colour.
For lipids, you'll use the emulsion test with ethanol and water, which creates a cloudy white emulsion if fats are present. The Biuret test for proteins uses two solutions (Biuret A and B) that turn the sample lilac-purple when proteins are detected.
Safety note: Ethanol is highly flammable, so keep it away from Bunsen burners during the lipid test!

Investigating Photosynthesis and Oxygen Production
This brilliant practical lets you actually see photosynthesis happening! Using an aquatic plant under water, you'll count the oxygen bubbles produced and discover how light intensity affects the rate of this vital process.
The setup is quite ingenious - your plant sits under an inverted funnel with a boiling tube above to collect the oxygen gas. The water contains sodium hydrogencarbonate to provide carbon dioxide for photosynthesis. A glass tank surrounds everything to prevent temperature changes from affecting your results.
By moving the lamp different distances away, you're changing the light intensity (your independent variable). Count the bubbles produced in a set time period - this is your dependent variable. You'll find that brighter light generally produces more oxygen, showing faster photosynthesis rates.
Smart setup: The glass tank acts as a heat shield, keeping temperature constant so you're only testing the effect of light intensity!
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Essential Chemistry Practical Activities for Paper 1
Ever wondered how scientists study tiny cells or test what's in your food? These five essential biology practicals will teach you the hands-on skills you need to investigate living organisms. From peering into onion cells under a microscope to watching... Show more

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Using a Microscope to Study Cells
Want to see the incredible world inside an onion? This practical shows you how to prepare a specimen and use a microscope properly. You'll need to carefully peel off a thin layer of epidermal tissue from an onion using tweezers.
The secret to getting a clear image is proper preparation. Place your tissue sample on a glass slide with a drop of water, then add iodine to stain the cells. This makes the cell structures much easier to spot under the microscope.
Using the microscope takes practice, but it's quite straightforward once you know the steps. Always start with the lowest-powered objective lens, use the coarse adjustment knob to get roughly in focus, then fine-tune with the fine adjustment knob. Remember to move the stage down gradually whilst looking through the eyepiece.
Top tip: Never force the adjustment knobs - gentle movements prevent damage to both the slide and the microscope lens!

Sign up to see the content. It's free!
- Access to all documents
- Improve your grades
- Join milions of students
Investigating Osmosis with Potato Cylinders
This osmosis experiment shows how water moves through cell membranes - something that's happening in your body right now! You'll cut identical potato cylinders using a cork borer and scalpel, then watch what happens when you place them in different concentrations of sugar solution.
The key to reliable results is making everything identical at the start. All cylinders must be the same diameter and length, and you'll need to measure their mass accurately. Each cylinder goes into a different boiling tube with various sugar concentrations, including pure distilled water as a control.
After leaving them for a set time, you'll measure the cylinders again. Some will have gained mass (water moved in), whilst others will have lost mass (water moved out). This demonstrates how osmosis works - water always moves from areas of low solute concentration to high solute concentration.
Remember: Blot the cylinders dry before final measurements to get accurate results!

Sign up to see the content. It's free!
- Access to all documents
- Improve your grades
- Join milions of students
Testing How pH Affects Enzyme Activity
Enzymes are biological catalysts that speed up reactions, but they're incredibly fussy about conditions! This practical uses amylase enzyme to break down starch into simpler sugars, and you'll discover how pH affects the reaction speed.
The clever part is using iodine as an indicator. When starch is present, iodine turns blue-black, but when the starch gets broken down into maltose, the iodine stays its normal colour. You'll test a drop of your reaction mixture every 10 seconds until the colour change stops happening.
Different pH levels dramatically affect enzyme performance. At pH 7 (neutral), amylase works efficiently and completes the reaction in about 60 seconds. However, at extreme pH values like pH 14, the enzyme becomes denatured and stops working entirely.
Key insight: Enzymes have an optimal pH range - step outside it and they lose their shape and function!

Sign up to see the content. It's free!
- Access to all documents
- Improve your grades
- Join milions of students
Food Tests - Detecting Nutrients
These four food tests help you identify what nutrients are lurking in different foods - it's like being a food detective! Each test uses a specific reagent that produces a distinctive colour change when the target nutrient is present.
Benedict's test for sugars involves heating your sample with Benedict's solution. A positive result shows a colour change from light blue to green, yellow, orange, or brick-red depending on sugar concentration. The iodine test for starch is simpler - just add a few drops and look for the characteristic blue-black colour.
For lipids, you'll use the emulsion test with ethanol and water, which creates a cloudy white emulsion if fats are present. The Biuret test for proteins uses two solutions (Biuret A and B) that turn the sample lilac-purple when proteins are detected.
Safety note: Ethanol is highly flammable, so keep it away from Bunsen burners during the lipid test!

Sign up to see the content. It's free!
- Access to all documents
- Improve your grades
- Join milions of students
Investigating Photosynthesis and Oxygen Production
This brilliant practical lets you actually see photosynthesis happening! Using an aquatic plant under water, you'll count the oxygen bubbles produced and discover how light intensity affects the rate of this vital process.
The setup is quite ingenious - your plant sits under an inverted funnel with a boiling tube above to collect the oxygen gas. The water contains sodium hydrogencarbonate to provide carbon dioxide for photosynthesis. A glass tank surrounds everything to prevent temperature changes from affecting your results.
By moving the lamp different distances away, you're changing the light intensity (your independent variable). Count the bubbles produced in a set time period - this is your dependent variable. You'll find that brighter light generally produces more oxygen, showing faster photosynthesis rates.
Smart setup: The glass tank acts as a heat shield, keeping temperature constant so you're only testing the effect of light intensity!
We thought you’d never ask...
What is the Knowunity AI companion?
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
Where can I download the Knowunity app?
You can download the app from Google Play Store and Apple App Store.
Is Knowunity really free of charge?
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
Similar content
Most popular content: Experiment
9Most popular content in Biology
9Most popular content
9Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.