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Here's a bit of high school chemistry for you guys.
(Those of you who remember high school chemistry, please let me know if I've messed up anywhere in my calcuations. Anything important, anyway. I'm going to be doing a fair amount of rounding and stuff. Ballpark figures are good enough for this.)
Do you know what a calorie is? It's a unit of energy. Specifically, heat energy. Even more specifically, it's defined as the amount of energy required to raise 1 gram of water by 1 degree celcius.
So, if you were to take, say, 1 cup of water (approx 237 grams) at the freezing point (0 degrees celcius) and raise it to body temperature (aprox 37 degrees celcius), it would take about 8800 calories (237 * 37, rounded to two significant digits).
Now, if that water happened to be in the form of ice, it would take even more heat. You need almost 80 calories to turn a gram of ice at 0 degrees into a gram of water. So, if you had 1 cup of ice, it would take about 19,000 calories (237 * 80, rounded) to turn it into water. Discounting the density change and whatever. Close enough.
Which means that to take 1 cup of ice and raise it to body temperature, you'd need at least 28,000 calories. More if it was below the 0 degree mark when it started.
Sounds pretty impressive, doesn't it?
How about this? Let's increase the amount of ice we're talking about to 2 liters. We're all familiar with the size of a 2 liter soda bottle. So let's take those 2 liters of ice, melt them, raise their temperature to the boiling point, and then add the extra energy needed to turn them into steam.
(Take a big pasta pot, dump the ice in, let it melt, then boil it off completely. That'll probably take a few hours, even with the cooktop set to high heat.)
The density of water is 1 g/ml. So we've got 2000 grams. (Which is 2 kg, which is a little shy of four and a half pounds.) Solid ice. Takes 80 calories per gram to melt that. Another 100 to raise it to the boiling point (100 celcius). And then another 540 to turn that boiling water into steam. That's 720 calories per gram. Multiply by 2000, and you've got 1,440,000 calories. Call it 1.4 million.
You know what? Let's make it five pounds of ice. A nice, big 5lb bag of ice. That's about 2300 grams, which brings our calorie total up to about 1.6 million.
That sounds like a heck of a lot, doesn't it?
Well, it should. It's enough energy to vaporize five pounds of ice.
But now you're looking at me funny. Because you're familiar with calories. You eat them every day. And if it takes 28,000 of them to bring a cup of ice up to body temperature, then we've got an idea for a heck of a diet, don't we?
Well, here's the thing. The calories listed on food packs? Those are actually kilocalories. There are 1000 calories per kcal. So, in food terms, we're actually talking a mere 28.
Which is still not bad. You can feel a little less guilty about that cup of ice cream, knowing that you're burning about 28 calories just to bring it up to body temperature. (Who cares if it's 250 calories per cup?)
But remember that bigger chunk of ice? The one we vaporized? That took 1.6 million calories. That's 1,600 kcal. Sound like a high number?
US RDA for an average adult human female is a 2,000 calorie/day diet. 2,500 if you're male, since males are a little larger than females. Most of us eat more than that. Every day.
That's how much it takes to make our bodies work.
Just a little something to think about.
(Those of you who remember high school chemistry, please let me know if I've messed up anywhere in my calcuations. Anything important, anyway. I'm going to be doing a fair amount of rounding and stuff. Ballpark figures are good enough for this.)
Do you know what a calorie is? It's a unit of energy. Specifically, heat energy. Even more specifically, it's defined as the amount of energy required to raise 1 gram of water by 1 degree celcius.
So, if you were to take, say, 1 cup of water (approx 237 grams) at the freezing point (0 degrees celcius) and raise it to body temperature (aprox 37 degrees celcius), it would take about 8800 calories (237 * 37, rounded to two significant digits).
Now, if that water happened to be in the form of ice, it would take even more heat. You need almost 80 calories to turn a gram of ice at 0 degrees into a gram of water. So, if you had 1 cup of ice, it would take about 19,000 calories (237 * 80, rounded) to turn it into water. Discounting the density change and whatever. Close enough.
Which means that to take 1 cup of ice and raise it to body temperature, you'd need at least 28,000 calories. More if it was below the 0 degree mark when it started.
Sounds pretty impressive, doesn't it?
How about this? Let's increase the amount of ice we're talking about to 2 liters. We're all familiar with the size of a 2 liter soda bottle. So let's take those 2 liters of ice, melt them, raise their temperature to the boiling point, and then add the extra energy needed to turn them into steam.
(Take a big pasta pot, dump the ice in, let it melt, then boil it off completely. That'll probably take a few hours, even with the cooktop set to high heat.)
The density of water is 1 g/ml. So we've got 2000 grams. (Which is 2 kg, which is a little shy of four and a half pounds.) Solid ice. Takes 80 calories per gram to melt that. Another 100 to raise it to the boiling point (100 celcius). And then another 540 to turn that boiling water into steam. That's 720 calories per gram. Multiply by 2000, and you've got 1,440,000 calories. Call it 1.4 million.
You know what? Let's make it five pounds of ice. A nice, big 5lb bag of ice. That's about 2300 grams, which brings our calorie total up to about 1.6 million.
That sounds like a heck of a lot, doesn't it?
Well, it should. It's enough energy to vaporize five pounds of ice.
But now you're looking at me funny. Because you're familiar with calories. You eat them every day. And if it takes 28,000 of them to bring a cup of ice up to body temperature, then we've got an idea for a heck of a diet, don't we?
Well, here's the thing. The calories listed on food packs? Those are actually kilocalories. There are 1000 calories per kcal. So, in food terms, we're actually talking a mere 28.
Which is still not bad. You can feel a little less guilty about that cup of ice cream, knowing that you're burning about 28 calories just to bring it up to body temperature. (Who cares if it's 250 calories per cup?)
But remember that bigger chunk of ice? The one we vaporized? That took 1.6 million calories. That's 1,600 kcal. Sound like a high number?
US RDA for an average adult human female is a 2,000 calorie/day diet. 2,500 if you're male, since males are a little larger than females. Most of us eat more than that. Every day.
That's how much it takes to make our bodies work.
Just a little something to think about.
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*sigh*
Life's not fair, is it?
See ya,
Anna.