Topic
Kitchen science
17 articles
Chemistry
Why does glue stick?
A liquid goes on, and a minute later two things cannot be separated. The obvious answer involves it seeping into holes and gripping, which cannot be right, because glue sticks perfectly well to a sheet of glass.
Chemistry
Why can’t you un-fry an egg?
Melt butter and it sets again when it cools. Heat an egg white and it turns from clear jelly to white rubber and stays there forever. Nothing was added, nothing escaped, and in 2015 a laboratory in Australia partly reversed it anyway.
Chemistry
Why does shaking a fizzy drink make it explode?
Everybody knows a shaken can will soak you, and everybody assumes that shaking somehow pumps it up. Measure the push inside before and afterward and you get the same answer twice. Something else entirely is being changed by all that rattling.
Chemistry
Why does blowing kill a candle but feed a fire?
One breath ends a birthday candle. The same breath, aimed at a campfire, makes it roar. Nothing about your lungs changed in between, so the difference has to be hiding inside the two fires.
Chemistry
Why does bread go stale faster in the fridge?
The fridge keeps milk drinkable and stops cheese sweating, so a loaf ought to be safe in there too. Instead it comes out hard and crumbly by the second day. Nothing has dried out, nothing has escaped, and the loaf weighs exactly what it did going in.
Chemistry
Why does salt melt ice?
Scatter salt on a frozen step and the ice retreats, even though the salt is exactly as cold as everything else. Nothing has been warmed and nothing has been dissolved away. The salt wins by interfering with traffic you never knew was there.
Physics
Why does toast land butter-side down?
Everybody assumes this is a joke about bad luck, or that the butter weighs one side down. Ten thousand drops by a thousand schoolchildren say it is real, and the culprit turns out to be the height of your kitchen table.
Biology
Why does a cut apple turn brown?
A whole apple sits in the fruit bowl all week and looks the same on Sunday as it did on Monday. Cut one at breakfast and it is the color of weak tea by lunchtime. Nothing was added to it.
Chemistry
Why does a cake need baking powder?
Leave it out and the cake comes out flat and heavy, and nothing else in the bowl has changed. So what is half a teaspoon of white powder doing that a pound of flour, sugar, butter and eggs cannot?
Chemistry
Why does ice float when almost every other solid sinks?
Drop a chip of hard candle wax into a pool of melted wax and it sinks. Almost every solid sinks in a puddle of itself. Ice does the opposite, and one feeble, fussy grip between molecules is the reason.
Biology
Why doesn’t your stomach digest itself?
Your stomach can take a chicken drumstick apart in about two hours. It is built from the same stuff as the drumstick. So why is it still there?
Chemistry
Why do onions make you cry?
A whole onion can sit in the kitchen for a month without bothering anybody. Cut it, and within seconds something invisible has crossed the room to your eyes. It was not inside the onion a moment earlier.
Biology
Why did sailors’ old wounds open up again?
A man on Anson’s ship had been shot more than fifty years earlier, and the scar had healed long ago. Months from land, it opened again, with nothing touching it.
Chemistry
Why does soap get grease off a plate when water won’t?
Hold a greasy plate under a running tap and the water slides off, leaving the grease exactly where it was. One drop of dish soap and it is gone. Nothing burned it away, and nothing melted it.
Physics
Why is the back of the fridge warm?
Reach around the back of a refrigerator and the metal is warm. The one machine in the house whose whole job is making things cold turns out to be heating your kitchen, and the reason is sealed inside a pipe.
Chemistry
Why does toast taste different from bread?
Nothing goes into the toaster except a slice of bread, and the slice comes out lighter than it went in. So where does the smell of toast come from?
Chemistry
Why does popcorn pop?
A pan of hard yellow beads goes quiet, then starts firing. Nothing is added to it and no kernel gains a single gram. So where does all that white come from?