3 cool kitchen lifehacks

Three super scientific lifehacks!

Safe­ty pre­cau­tions

Per­form this ex­per­i­ment only un­der adult su­per­vi­sion.


  • elec­tric ket­tle;
  • Coca-Cola;
  • salt;
  • pep­per;
  • bal­loon;
  • raw egg;
  • boiled egg.

Step-by-step in­struc­tions

  • 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!

Process de­scrip­tion

  • 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.