Staying Safe with Acids and Alkalis

Hello everyone! Have you ever used lemon juice in your food or cleaned the kitchen with a spray cleaner? If so, you've used acids and alkalis! They are super useful in our daily lives and in the science lab. But, just like a sharp knife, they can be dangerous if we don't handle them correctly.

In these notes, we'll learn about the potential dangers of acids and alkalis, why you should never mix cleaning products, and the most important first aid steps if an accident happens. Knowing this will help you stay safe in the lab and at home!


The Dangers of Acids and Alkalis

Irritating vs. Corrosive: What's the Difference?

When we say a chemical is hazardous, we mean it can cause harm. For acids and alkalis, the two main dangers are that they can be irritating or corrosive. Don't worry if these words seem tricky at first, we'll break them down!

Think of it like this:

  • An irritant is like an annoying little brother who keeps poking you. It's not causing serious damage, but it's making your skin red, itchy, and uncomfortable.
  • A corrosive substance is like a hungry monster. It doesn't just poke you; it tries to eat away at whatever it touches! It can cause very serious, permanent damage.

What does irritating mean?

An irritating chemical is one that can cause your skin to become red, swollen, itchy, or develop a rash. It usually affects the surface of the skin.

Examples: A weak acid like vinegar or lemon juice might sting a lot if you get it in a small cut on your finger. This is an irritating effect.


What does corrosive mean?

A corrosive chemical is much more dangerous. It can destroy and permanently damage substances it comes into contact with. This includes your skin, your eyes, and even metal!

  • When a corrosive chemical touches your skin, it can cause a severe chemical burn, destroying the skin tissue.
  • If it gets in your eyes, it can cause blindness.
  • This is why we must be extremely careful with strong acids and alkalis in the lab!

Examples: Concentrated laboratory acids are corrosive. Strong alkalis, like the chemicals used in oven cleaners or to unblock drains, are also very corrosive.

Did you know?

If you spill a strong alkali on your hands, it can feel slippery or soapy. This isn't because the chemical is like soap! It's because the alkali is reacting with the natural fats in your skin and turning them into soap! This is a sign that the alkali is causing damage.

Key Takeaway

Acids and alkalis can be harmful. Irritating substances cause discomfort like rashes, while corrosive substances cause serious destruction and burns. Always treat these chemicals with respect and care!


The Danger of Mixing Cleaning Products

A Very Bad Recipe!

You might think that if one cleaning product is good, mixing two together will make them extra-powerful. This is a very common but extremely dangerous mistake.

NEVER, EVER mix different cleaning products together!

Why is it so hazardous? When you mix certain chemicals, they can react to create completely new substances, often in the form of poisonous gases that you can't see!

A Common and Dangerous Mix: Bleach + Ammonia

This is one of the most dangerous household combinations.

  • Bleach (a common cleaner) is an alkaline substance.
  • Many glass cleaners or floor cleaners contain a chemical called ammonia.

When you mix these two together, they react and produce a poisonous gas called chloramine gas. Breathing in this gas can cause:

  • Coughing and chest pain
  • Shortness of breath
  • Watery eyes
  • Damage to your lungs
Another Dangerous Mix: Bleach + Acidic Cleaners

If you mix bleach with an acidic cleaner (like some toilet bowl cleaners), you can create pure chlorine gas. This is another highly toxic gas that was even used as a chemical weapon in wars. It is extremely dangerous to breathe in.

Common Mistakes to Avoid

Mistake #1: "I'll just use one cleaner, and then use another one right after without rinsing."
Why it's bad: The residue from the first cleaner can still be on the surface and will react with the second cleaner. Always rinse with water between using different products.

Mistake #2: "I want the toilet to be extra clean, so I'll pour in some bleach and some toilet bowl cleaner."
Why it's bad: As we learned, this can create poisonous chlorine gas in a small, enclosed space like a bathroom.

Golden Rule: Read the safety instructions and warnings on the label of every cleaning product before you use it!

Key Takeaway

Mixing common cleaning products, especially anything containing bleach with products containing ammonia or acid, is extremely hazardous and can create poisonous gases. Always use one cleaner at a time and read the label!


What to Do in an Accident (Emergency Treatment)

Stay Calm and Act Fast!

If an accident happens with an acid or alkali, it's important not to panic. The first few seconds are critical. The number one rule is to wash the chemical away with lots of water.

Step-by-Step Emergency Guide

1. If a chemical spills on your skin or clothes:

  • Tell your teacher or an adult IMMEDIATELY.
  • Carefully remove any clothing that has the chemical on it. The fabric can trap the chemical against your skin and make the injury worse.
  • Go to the nearest tap or safety shower and rinse the affected skin with a large amount of cool, running water.
  • Keep rinsing for at least 15-20 minutes. This might feel like a long time, but it's crucial to make sure all the chemical is washed away.

2. If a chemical splashes in your eyes:

  • This is a very serious emergency. Yell for help and tell an adult IMMEDIATELY.
  • Get to an eyewash station or a tap right away.
  • Hold your eye open (use your fingers if you have to) and rinse it with a gentle, steady stream of cool water.
  • Continue rinsing for at least 15-20 minutes to flush out the chemical completely.
  • You must get medical attention after this.
Quick Review Box

Acid/Alkali on Skin? → RINSE with lots of water for 15-20 mins. TELL an adult.
Acid/Alkali in Eye? → RINSE with lots of water for 15-20 mins. GET HELP FAST.


Important: What NOT To Do!

You might have learned that acids and alkalis "cancel each other out" (a process called neutralisation). You might think it's a good idea to put an alkali on an acid burn to neutralise it.

DO NOT DO THIS!

Trying to neutralise a chemical burn on the skin is very dangerous. The reaction between the acid and alkali can produce a lot of heat, which will make the burn much, much worse. The safest and best thing to do is always just to use large amounts of water.

Key Takeaway

In an accident with acids or alkalis, the most important step is immediate rinsing with plenty of cool, running water for 15-20 minutes. Never try to neutralise a chemical on your skin. Always inform a teacher or adult as soon as possible.