The “hard” in having a hard-boiled egg on the top of Mount Everest.
Have you ever been on the top of Mount Everest enjoining the view while eating a freshly hard-boiled egg? I sure haven’t, and I know for a fact that you and no one else on this planet have either. This is because it’s physically impossible.
Forget about all the hassle by safely bringing a raw egg to the top without breaking, that’s the easy part. The real problem starts when the egg is in the water.
Let’s break down why this is in the context of science.
I’m guessing that exactly where you are reading this you’d be able to boil water at around 100°C. You would think this was a universal physical law, but this is actually not the case.
The boiling point is a transition phase of matter, in this case water, going from liquid to gas. At this phase the water has exactly enough energy, in form of temperature, to overcome the atmospheric pressure and be released into the air. Wait, atmospheric pressure what?
Atmospheric pressure is basically a measure of how much weight there is above and surrounding a specific object. For example, when you go deeper under water the pressure increases. This is because you, the object, now have more water above and around you. This works the same way with air. So even though the air is much lighter than water, you will still have less air on top of you when you are higher up. Makes sense right?
But how is this related to boiling water? You see, the higher the pressure is, the more weight is sitting on top of the water pushing it down. This makes it “heavier” for the particles to transition into vapour and they would need more energy to exceed this extra weight pushing it down.
So when you are higher up and the pressure is lower, like on the top of Mount Everest, it is much easier for water to go from liquid to gas. This means that the water requires less energy, hence temperature, to boil. Actually, for every increase of 300 meters in altitude, the water will boil at 1°C lower. Since Mount Everest is majestically 8,848 meters high, the boiling point of water will be as low as 70°C.
Now that we got all the physics out of the way, let’s talk biology.
If you go to the gym or are interested in nutrition you probably know that eggs consist of much protein. The different proteins in the egg have different properties and are built up differently. You can visualise the shape of them as a long string that is wrapped up as a ball.
As you know with eggs, they go hard when you boil them. This is because the high temperature causes the proteins to unwrap from their normal soft “ball” shape and leaves them as many hard long strings. Here’s a video explaining this in more depth if you are interested.
The different parts of the egg are built up by different proteins which turn into strings at different temperatures. The egg yolk will unwrap at 65-70°C, while the egg white needs to reach around 80°C to go hard.
Since the water at Mt Everest will boil at 70°C, it will never reach the temperature for the egg white proteins to unwrap. And no matter how long you try to boil the egg in the water you’ll only end up with a hard egg yolk and soft egg white. Pretty disappointing huh?
However, there is a loophole. Different liquids have different boiling points. So although water doesn’t get warm enough to harden the egg white, other liquids like oil do.
So next time you are planning a trip to the peak of Mount Everest, make sure to bring oil instead of water so you can enjoy a successfully freshly hard-boiled egg while looking over the world.
Let me know what the boiling point is where you are reading this. Use this link to see how high you are above sea level. Remember, the boiling point decreases with 1°C every 300 meters of elevation.