Why Does Soapy Water Kill Ants: The Science Behind How it Works

Having ants around the house can be annoying, especially when they start to invade your kitchen. Soapy water is a common household item that can be used to kill ants and keep them away simply because of the surfactants in the soap.

Ants typically can float in water, but when there’s a presence of surfactant in the water, it breaks the surface tension. This then causes the ants to be pulled under and eventually drowns them.

close up of black ant on stick

It’s not just the soap that does the killing. The water is also necessary for the process to work. Water is an integral part of the soapy water mixture because it helps to spread the soap throughout the liquid.

When ants come into contact with soapy water, they are immediately covered in it. This causes them to start sinking because they are now coated in a substance that is denser than they are.

An In-Depth Explanation of How Soapy Water Works as an Ant Killer

Typically, ants can float on top of water because their bodies are hydrophobic, meaning they repel water. This is due to a thin layer of oil that covers their bodies and keeps them dry.

When this natural barrier is removed, ants are no longer able to float. The oil layer also helps ants keep their grip as they walk on surfaces. Without this layer, they lose their grip and start to slip.

The process of how soapy water kills ants can be explained by the fact that soap is a surfactant. A surfactant is a substance that lowers the surface tension of a liquid, which allows it to spread out more easily.

When mixed with water, soap creates bubbles because it allows the water to spread out and form a thin layer around the ants.

The bubbles created by the soap trap air inside of them. Ants rely on their ability to breathe through their bodies to survive.

When they are coated in soapy water, they can no longer get the oxygen they need to breathe. This eventually leads to their death.

How to Use Soapy Water to Get Rid of Ants

There are plenty of different methods people use to get rid of ants, but perhaps one of the most effective is a simple soapy water solution.

This basic concoction can be easily made at home, and it works by suffocating the ants rather than killing them with harsh chemical poisons.

This method is proven to be effective in killing ants without resorting to harmful chemicals.

spray bottle on table

To use this method, here’s what you need:

  • A spray bottle
  • Water
  • Soap

The Procedure

1) Mix Equal Parts of Soap and Water

The first step is to mix equal parts of soap and water in the spray bottle. Any type of soap can be used, but it’s important to make sure that it’s diluted properly. Otherwise, the ants will be able to withstand the solution.

2) Spray the Soapy Water on the Ants

Look for an ant trail and spray the soapy water directly on it. Make sure to target as many ants as possible, as well as their nests if you can find them. Soak the area well and wait for the ants to start dying.

It’s important to note that soapy water isn’t just effective at killing ants. It can also be used to kill other pests, such as spiders, cockroaches, and even flies.

If you have a problem with any of these pests, give this method a try and see for yourself how well it works.

3) Repeat as Necessary

The soapy water method is most effective when it’s used regularly. Ants will eventually come back, so it’s important to be vigilant and treat the problem as soon as it arises.

Repeat this process as needed to keep ants away for good.

What Kind of Soap Works Best for Killing Ants?

There is no single kind of soap that works best for killing ants. Rather, the effectiveness of different soaps will depend on several different factors, including the specific species of ant that you are dealing with, as well as their general living conditions.

For example, some types of ants may live in more protected areas and will therefore be less susceptible to the effects of a strong detergent.

In addition, certain species may have thicker or tougher exoskeletons than others, which could make them more resilient to certain types of cleansers.

At the same time, it is important to keep in mind that all soaps work by essentially breaking down the outer layer of an insect’s exoskeleton.

This not only weakens the ants’ body structure but also allows for easier penetration of any pesticides or other agents that you might apply in combination with your soap solution.

So while one type of soap may perform better than another in some situations, it is ultimately best to experiment with a variety of different cleaners until you find one that works well for your particular ants.

human pouring laundry detergent on cup

Laundry Detergent

One of the most commonly used soaps for killing ants is laundry detergent. Laundry detergents contain strong chemicals that can penetrate even the thickest of ant exoskeletons and destroy their internal organs.

Additionally, as with many other household cleaners, laundry detergents are readily available in most homes and relatively inexpensive to purchase.

This makes them an easy and convenient option when it comes to dealing with pesky ants.

However, with that being said, there are some downsides to using laundry detergent to kill ants. For one thing, if towels or clothing are placed in areas where ants frequently appear, a residual film of soap may end up on these items and create white streaks.

Make sure that you mix the laundry detergent with water before using it on ants, as undiluted solutions can actually cause more problems than they solve.

In addition, always test the solution on a small area first to make sure that it won’t damage your floors or other surfaces. 1 cup of laundry detergent mixed with ½ gallon of water is usually a good starting point, but you may need to adjust the ratio depending on the strength of your detergent.

Bath Soap

In general, bath soap tends to be the most effective choice when it comes to eliminating ants. Because of its high concentration of surfactants, bath soap can penetrate the hard outer shells that many ant species possess, killing them quickly and effectively.

Additionally, bath soap contains a number of other ingredients that make it a powerful natural insecticide, including antibacterial chemicals and oils that help to repel ants and prevent them from coming back.

They’re a popular choice against carpenter ants, fire ants, and pharaoh ants.

Melt a bar of bath soap in a pot of boiling water, then let the solution cool before using it. Once it has cooled, pour the soap into a spray bottle mixed with equal parts of water and spray it to areas where ants are present.

You can also use a sponge or cloth to apply the soap directly to the ants.

Dish Soap

Like laundry detergent, dish soap is also a powerful cleaning agent that can be used to kill ants. In fact, dish soap is often even more effective than laundry detergent because it contains higher concentrations of surfactants.

Preparation is also fairly easy as dish soaps usually come in concentrated liquid form – this means that you don’t need to melt the soap before using it, as you would with bath soap.

To use dish soap to kill ants, simply mix a solution of one part dish soap with three parts water and pour it into a spray bottle. Then, go around your house and spray the solution onto any areas where ants are present.

Final Thoughts

Soapy water is a great way to kill ants because it contains high concentrations of surfactants that can penetrate the hard outer shells of many ant species.

When soapy water gets in contact with an ant, water will be able to penetrate its body, making it difficult for ants to float. In turn, this will cause ants to eventually drown.

You can use any type of soap, but bath soap and dish soap seem to work the best. Just make sure that you dilute the soap with water before using it, and always test it on a small area first to make sure it won’t damage your floors or surfaces.