Production of oxygen in a submarine

In summary, the conversation discusses the chemical reaction that occurs when burning a candle containing iron and sodium chlorate. The burning of iron produces heat and oxygen, which then reacts with the sodium chlorate to release even more oxygen. The amount of iron present in the candle is only about 10% by weight, and only half of it is actually used in the reaction. The purpose of the iron is to provide the heat needed for the reaction to occur.
  • #1

I was watching the following video.

Around 17:00 the following is said:

Okay. It wasn't until I got off the sub,
when I totally understood what was going on here.
But the two main chemicals in this candle were iron and sodium Chlorate.
When you burn iron,
that's adding oxygen to the iron and you're creating iron oxide.
You're actually creating heat. That's the burning of the candle.
But when you do that, there's also sodium chlorate in the candle.
And that heat from the iron oxide is liberating oxygen from the sodium chlorate.
and in doing so you actually get more oxygen from the chemical reaction.

I tried to balance the chemical equation as presented in the video. Please have a look below. I don't see how the production of iron oxide yields more oxygen in the entire reaction. The heating of sodium chlorate produces three molecules of oxygen and these molecules are then used to oxidize iron. Where am I going wrong? Thanks, in advance!

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  • #2
Any idea how much iron is in there ?
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  • #3
hmmm27 said:
Any idea how much iron is in there ?

Don't know! What am I missing here?

PS: I think I get it now.

The reaction of iron with oxygen is there only to provide heat so that sodium chlorate could break down. In other words, there isn't that much of iron there; only enough to provide the required heat. Therefore, more oxygen is released from the break down of sodium chlorate.


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1. How is oxygen produced in a submarine?

Oxygen is produced in a submarine through a process called electrolysis, where water molecules are split into oxygen and hydrogen using an electric current. This oxygen is then stored in tanks and distributed throughout the submarine for use by the crew.

2. How much oxygen is produced in a submarine?

The amount of oxygen produced in a submarine depends on the size and capacity of the electrolysis system. On average, a submarine produces enough oxygen to sustain its crew for several weeks.

3. Is the oxygen produced in a submarine safe to breathe?

Yes, the oxygen produced in a submarine is safe to breathe. The electrolysis process removes impurities from the water, ensuring that the oxygen produced is of high quality and suitable for human consumption.

4. What happens if the oxygen supply in a submarine runs out?

In case of an emergency, submarines are equipped with emergency oxygen supplies in the form of oxygen candles or chemical oxygen generators. These can provide enough oxygen for the crew to survive until they can resurface or receive assistance.

5. Can the production of oxygen in a submarine be affected by external factors?

Yes, the production of oxygen in a submarine can be affected by external factors such as changes in water pressure, temperature, and salinity. Submarines are designed to account for these factors and have systems in place to ensure a steady supply of oxygen for the crew.