Category: Recipe of the Week

Continuing our new series of chemical recipes, we bring you week 8 – sodium hydroxide (NaOH).

Remember that when preparing any of our recipes, you should always wear appropriate PPE.

What is sodium hydroxide?

Also known as caustic soda or lye, this is a very corrosive substance that can cause chemical burns, usually used as a solution as these are cheaper and easier to handle, or as a solid. It is highly soluble in water, continuing to absorb moisture until it’s dissolved. It is the most widely used industrial alkali.

Sodium hydroxide is used in papermaking, soap making, the refining of petroleum, and is commonly found in household drain and oven cleaners.

Click here to view the PDF recipe card to either save to your local files or add it as a bookmark to your browser.

Scan the QR codes for classroom experiments to follow with your safe and prepared sodium hydroxide.

Continuing our new series of chemical recipes, we bring you week 7 – Janus Green B (C₃₀H₃₁CIN₆).

Remember that when preparing any of our recipes, you should always wear appropriate PPE.

What is Janus Green B?

Janus Green B is a dye and vital stain (a stain that can be applied to living cells without killing them) that changes colour to indicate the amount of oxygen present in an aqueous solution. A blue colour indicates the presence of oxygen whereas pink indicates absence. Before application, the powder is a dark green/black colour.

It is also known as Union Green B and Diazin Green S, and has been used in surgical and diagnostic procedures involving mitochondria, fungi, nucleic acids and chromosomes, among others.

Click here to view the PDF recipe card to either save to your local files or add it as a bookmark to your browser.

Scan the QR codes for classroom experiments to follow with your safe and prepared Janus Green B.

Continuing our new series of chemical recipes, we bring you week 6 – nutrient agar.

Remember that when preparing any of our recipes, you should always wear appropriate PPE.

What is nutrient agar?

A general purpose growth medium, nutrient agar is used for the cultivation of non-fibrous microbes, growing a variety of different types of fungi and bacteria.

It is used also for quality control and purity verification ahead of biochemical or serological testing, and for producing bacterial lawns for antibiotic sensitivity tests.

Click here to view the PDF recipe card to either save to your local files or add it as a bookmark to your browser.

Scan the QR code for classroom experiments to follow with your safe and prepared nutrient agar.

Continuing our new series of chemical recipes, we bring you week 5 – Benedict’s reagent (C₇H₁₀CuNa₂O₁₅S).

Remember that when preparing any of our recipes, you should always wear appropriate PPE.

What is Benedict’s reagent?

Also known as Benedict’s qualitative solution or Benedict’s solution, this chemical reagent is used in Benedict’s tests to detect the presence of certain reducing sugars such as hemiacetals, alpha-hydroxy-ketones, and aldehydes. It is named after the American chemist who discovered it, Stanley Rossiter Benedict.

Positive results caused by the presence of reducing substances cause a colour change from clear blue to brick red. Heating the reagent can check its purity – no changes in the clear blue colour shows that the reagent is pure.

Click here to view the PDF recipe card to either save to your local files or add it as a bookmark to your browser.

Scan the QR codes for classroom experiments to follow with your safe and prepared Benedict’s reagent.

Continuing our new series of chemical recipes, we bring you week 4 – ammonia solution (NH₄OH).

Remember that when preparing any of our recipes, you should always wear appropriate PPE.

What is ammonia solution?

Also known as ammonium hydroxide, this solution of ammonia salts in water is a colourless liquid with a strong odour.

It is used in household cleaners, food production (an additive with the E number E527 in the EU) and water treatment as a disinfectant.

Click here to view the PDF recipe card to either save to your local files or add it as a bookmark to your browser.

Scan the QR codes for classroom experiments to follow with your safe and prepared ammonia solution.

Continuing our new series of chemical recipes, we bring you week 3 – bicarbonate indicator (HCO₃).

Remember that when preparing any of our recipes, you should always wear appropriate PPE.

What is a bicarbonate indicator?

Also known as hydrogencarbonate indicator, this sensitive pH indicator is used within photosynthesis and respiration experiments to show the concentration of carbon dioxide within a liquid – as the level of carbon dioxide changes, the colour will also.

The initial cherry red colour will change to yellow if the carbon dioxide content exceeds 0.04% and pink/purple when it drops below 0.04%.

Click here to view the PDF recipe card to either save to your local files or add it as a bookmark to your browser.

Scan the QR codes for classroom experiments to follow with your safe and prepared bicarbonate indicator.

Continuing our new series of chemical recipes, we bring you week 2 – sulphuric acid (H₂SO₄).

Remember that when preparing any of our recipes, you should always wear appropriate PPE.

What is sulphuric acid?

Also known as oil of vitriol or hydrogen sulphate, this has a clear or brown oil-like appearance. It has dehydrating properties making it a highly reactive chemical which will corrode many metals and damage most organic materials on contact, so should be handled with caution.

Some of its uses include as a food starch modifier, in household cleaning products, within batteries, and for pen ink used in arts and crafts. It is associated with volcanic eruptions.

Click here to view the PDF recipe card to either save to your local files or add it as a bookmark to your browser.

Scan the QR codes for classroom experiments to follow with your safe and prepared sulphuric acid.

Coming every week, SciChem will be bringing you a ‘recipe of the week’. These handy PDFs will be downloadable so you can save them and refer back to them at any point, helping you build up an extensive library of useful chemical recipes that will aid in conducting classrooms experiments.

For the first week, our recipe is for Ethanoic Acid, also known as Acetic Acid.

What is ethanoic acid?

This chemical is used as an ingredient in vinegar (a 4-8% solution with water) and due to being inhospitable to bacteria, is used as a preserving agent. It goes by several names including ethylic acid, hydrogen acetate, acetic acid, and methanecarboxylic acid.

Its formula can be written as both CH₃COOH and C₂H₄O₂ – interchangeable depending on the context in which its chemical behaviours are being considered.

As well as being used as a food preservative and as a component in vinegar, as a weak acid it’s also used in photography and printing, as an antibiotic, and within sealants.

Download or bookmark your copy of the ethanoic acid recipe of the week.

Scan the QR codes for classroom experiments to follow with your safe and prepared ethanoic acid.