3 cool kitchen lifehacks
Three super scientific lifehacks!
Perform this experiment only under adult supervision.
- electric kettle;
- raw egg;
- boiled egg.
Take an electric kettle coated with limescale and rust. Pour some Coca-Cola into the kettle, and set the kettle to boil. Leave the hot Cola in the kettle for 20 minutes. Pour out the Cola and rinse the kettle with tap water. The rust and limescale are gone!
Sprinkle some salt and some pepper flakes on a plate. Electrify a balloon on your hair, then hold it to the mixture. Note that the pepper is attracted to the balloon!
Take two eggs: one raw, one boiled. Spin the raw egg – it spins unevenly and falls quickly. Spin the boiled egg – it spins smooth as a top!
- Water contains a number of iron oxides and a variety of dissolved salts, such as calcium carbonate СаСО₃ and magnesium carbonate MgСО₃. Over time, they precipitate on the surface of the heating element to form a white limescale or ginger mixture of rust and limescale. Coca-Cola contains phosphoric acid, which reacts with the scale to form soluble compounds that are easily washed away:
СаСО₃ + Н3PO₄ = Ca₂(PO₄)₃ + 3H₂O + 3CO₂
MgСО₃ + Н₃PO₄ = Mg₂(PO₄)₃ + 3H₂O + 3CO₂
Fe₂O₃ + 2Н₃PO₄ = 2FePO₄ + 3H₂O
Everything around us is made of atoms, which in turn consist of charged particles: protons and electrons. Protons are positively charged, while electrons are negatively charged. Normally, they compensate for each other, resulting in an object with a neutral charge. When two objects are subjected to frictional forces against each other, the surface atoms layer of one object can give some of its external electrons to the other. The object that gives up electrons gains a positive charge, and the object that accepts electrons gains a negative charge. When we rub a balloon on our hair, its surface accepts some electrons and it thus acquires a negative charge. An electric field appears around it, which can affect positively- and neutrally-charged objects. This is why the pepper flakes are attracted to the balloon. The salt, however, is not attracted to the balloon because its surface electrons are not very mobile, which allows it to remain unaffected by the balloon’s electrical charge.
Chicken eggs consist of a shell, a white, and a yolk. The yolk contributes to most of its mass, so the egg's center of mass is also in or near the yolk. When a raw egg is spun, its center of mass changes constantly because its yolk is mobile. This causes the egg to falter and destabilize. A boiled egg’s contents are effectively immobilized, and the location of its center of mass is fixed, allowing it to spin steadily and for much longer.