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Name: Erika Brown
Status: student
Age: 20s
Location: N/A
Country: N/A
Date: 2000

I am a photography student and I am working on a project where I am making film developer out of coffee. The recipe for the developer asks for Potassium Hydroxide. It requires me to mix this with baking soda, coffee, and water. I am quite concerned about mixing it with water after researching it because of all of the warnings say not to mix the two together. My question to you is how safe is it to mix Potassium Hydroxide with water?

I really have no idea what exactly can happen.

Thank you very much.

Solid potassium hydroxide, like solid sodium hydroxide, releases a large amount of heat when dissolved in water. To prevent overheating, add the potassium hydroxide TO THE WATER SLOWLY, not the other way around. The heat capacity of the water will help absorb the heat. If you want added precaution place the vessel in an ice bath.

Your concern for safety is commendable. Also wear eye shields and protective gloves. Even disposable latex or polyethylene gloves are adequate.

Vince Calder

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