Top 5 Christmas chemical experiments

Using chemistry to create the Christmas spirit!

Christ­mas is just around the cor­ner! Once you’ve cho­sen the per­fect gifts for your friends and fam­i­ly, it’s time to think about fun Christ­mas ac­tiv­i­ties. With just a lit­tle ef­fort, these 5 fes­tive ex­per­i­ments will help you dec­o­rate the house and fill it with the Christ­mas spir­it in no time!

Ar­ti­fi­cial snow

Want to spice up your Christ­mas dec­o­ra­tions with some ar­ti­fi­cial snow? Here’s how to make your own in just 5 min­utes!

You’ll need:

  • Di­a­pers (they con­tain sodi­um poly­acry­late, a chem­i­cal com­pound that ef­fec­tive­ly ab­sorbs liq­uid – and that’s ex­act­ly what you’ll need for this ex­per­i­ment);
  • A glass of wa­ter;
  • An emp­ty glass or con­tain­er.

How to:

  1. Cut open some di­a­pers and pour the con­tents (sodi­um poly­acry­late gran­ules) into a clean glass.
  2. Pour some wa­ter into an­oth­er clean glass (ap­prox­i­mate­ly 100 mL of wa­ter per 2–3 grams of gran­ules).
  3. Add the wa­ter to the sodi­um poly­acry­late gran­ules.
  4. Watch the sub­stance ab­sorb wa­ter and swell, sig­nif­i­cant­ly in­creas­ing in size and form­ing “snowflakes”!

The ab­sorb­ing sub­stance in di­a­pers is sodi­um poly­acry­late in gran­ule form. It can ab­sorb tremen­dous amounts of liq­uid — hun­dreds of times its own mass! Wa­ter pen­e­trates into the poly­acry­late gran­ules, and oc­cu­pies so much space in­side these gran­ules that they have to swell to ac­com­mo­date it, turn­ing into “snow.” Pre­cise­ly what you need for your Christ­mas dec­o­ra­tions! But be­ware, if you add too much wa­ter, it will turn into a jel­ly­like mass in­stead of “snow.” Just a note: with time, this “snow” may start los­ing shape as the wa­ter grad­u­al­ly evap­o­rates. You can, how­ev­er, re­store its shape – just add a bit more wa­ter! Store this ar­ti­fi­cial snow in an air­tight con­tain­er.

This snow isn’t ed­i­ble! Make sure to wash your hands af­ter play­ing with it.

Snow­fall in a bot­tle

Think you can only en­joy watch­ing snow­ fall out­side? Cre­ate your own mini-snow­storm in an or­di­nary plas­tic bot­tle!

For this ex­per­i­ment, you'll need:

  • Am­mo­ni­um chlo­ride (NH4­Cl) – 70 g;
  • Wa­ter (H2O);
  • An emp­ty plas­tic bot­tle;
  • A glass or an­oth­er emp­ty con­tain­er;
  • A pot of hot wa­ter (a heat­ed bath).

How to:

  1. Pour 70 g of am­mo­ni­um chlo­ride into a glass;
  2. Fill the glass with wa­ter up to the 500 mL mark and stir the con­tents (the salt won’t dis­solve com­plete­ly);
  3. Place the glass in the pot of hot wa­ter (chemists would re­fer to this as a heat­ed bath) and wa­ter un­til the salt dis­solves com­plete­ly;
  4. Quick­ly pour the hot so­lu­tion into a bot­tle and cap it. Once the so­lu­tion starts to cool down, you’ll see a beau­ti­ful snow­fall — salt crys­tals will pre­cip­i­tate out and fall down in the bot­tle, just like lit­tle snowflakes.

How does this snow­fall in a bot­tle work?

How much of a sub­stance can dis­solve in a glass of wa­ter? It re­al­ly de­pends on the prop­er­ties of the sub­stance and the tem­per­a­ture of the wa­ter. Here, we want to dis­solve more am­mo­ni­um chlo­ride than is pos­si­ble at room tem­per­a­ture; there­fore, we have to heat the so­lu­tion. And the solute dis­solves com­plete­ly in a mat­ter of min­utes! But as soon as the so­lu­tion starts to cool, all the ex­ces­s am­mo­ni­um chlo­ride has to pre­cip­i­tate out — and it falls to the bot­tom in the form of del­i­cate crys­tals. It looks like a real snow­storm!

Christ­mas or­na­ments

Chem­istry can help you work mag­ic! For in­stance, you can make sparkling Christ­mas or­na­ments that will look just as good as what you can buy in a store!

You’ll need:

  • Sil­ver ni­trate (Ag­NO3) – 0.5 g Ag­NO3 in 100 mL of wa­ter;
  • Sodi­um hy­drox­ide (NaOH) – 0.5 g NaOH in 100 mL of wa­ter;
  • Am­mo­nia so­lu­tion (3%) (NH3*H2O) – 5 mL;
  • Glu­cose (C6H12O6) – 0.15 g of glu­cose in 30 mL of wa­ter;
  • A glass flask or bot­tle;
  • Op­tion­al: a rib­bon and a short fir tree branch;
  • A pipette.

How to:

  1. Take a glass flask — it will serve as a base for your Christ­mas dec­o­ra­tion;
  2. Pour a so­lu­tion of sil­ver ni­trate into the flask. Drop by drop, add a so­lu­tion of sodi­um hy­drox­ide — it will form a brown pre­cip­i­tate;
  3. Drop by drop, add am­mo­nia to the flask — it should dis­solve the pre­cip­i­tate;
  4. At once, pour out all a glu­cose so­lu­tion into the flask. Shake the flask vig­or­ous­ly for 3–5 min­utes. You should see a shiny sil­very film form­ing on the walls of the flask;
  5. Pour the so­lu­tion out of the flask. Rinse the flask with wa­ter sev­er­al times;
  6. Add a rib­bon and a fir tree branch to the flask to fin­ish the dec­o­ra­tion. Done and done!

Where does the sil­very film in the flask come from?

First, you syn­the­size sil­ver(I) ox­ide (the brown pre­cip­i­tate) and then dis­solve it in am­mo­nia. It yields the tar­get sub­stance – sil­ver di­amine hy­drox­ide [Ag(NH₃)₂]OH – need­ed to cre­ate a mir­ror-like film. Fur­ther, you add glu­cose to re­duce the sil­ver, which pre­cip­i­tates out and forms a beau­ti­ful shiny coat­ing.

Make sure to wear pro­tec­tive gloves when con­duct­ing this ex­per­i­ment.

Sil­ver tree

In or­der to make a sil­ver tree, you’ll need:

  • A cop­per tree (cop­per plates fold­ed into a Christ­mas tree);
  • A so­lu­tion of sil­ver ni­trate Ag­NO3 (0.5 g of Ag­NO3 in 100 mL of wa­ter);
  • A beaker.

How to make a sil­ver Christ­mas tree:

  1. Set the cop­per tree in the beaker;
  2. Pour the so­lu­tion of sil­ver ni­trate into the beaker, com­plete­ly im­mers­ing the tree;
  3. Wait for sev­er­al min­utes — you’ll see sil­ver crys­tals ap­pear on the cop­per tree, and the so­lu­tion will grad­u­al­ly turn light-blue.

How does sil­ver coat the cop­per tree?

Once cop­per is added to the so­lu­tion of sil­ver ni­trate, it caus­es a sub­sti­tu­tion re­ac­tion. The re­ac­tion pro­ceeds as fol­lows: 2Ag­NO₃ + Cu = Cu(NO₃)₂ + 2Ag. Sil­ver and cop­per swap places: cop­per en­ters the so­lu­tion, and sil­ver pre­cip­i­tates out in the form of met­al. The so­lu­tion turns light-blue due to the for­ma­tion of cop­per(II) ni­trate – the cop­per ions tint the so­lu­tion blue.

Make sure to wear pro­tec­tive gloves when con­duct­ing this ex­per­i­ment.

Frost­work

You’ve like­ly seen an abun­dance of Christ­mas tree or­na­ments dec­o­rat­ed with frost­-like pat­terns. You, too, can eas­i­ly draw your own icy pat­terns on any piece of glass!

How to:

  • Car­bamide, or urea ((NH2)2CO) – 300 g;
  • Wa­ter (H2O) – 50 mL;
  • A glass;
  • A small piece of glass;
  • A paint­brush.

How to cre­ate pat­terns on a glass us­ing car­bamide?

  1. Pour 300 g of car­bamide into a glass. Add 50 mL of hot wa­ter and mix thor­ough­ly. The car­bamide will start dis­solv­ing in the wa­ter, but won’t dis­solve com­plete­ly be­cause there is too much of it);
  2. Dip a paint­brush into the so­lu­tion:
  3. Take a piece of glass and make sev­er­al strokes with the paint­brush to ap­ply the so­lu­tion to the glass;
  4. Wait for sev­er­al min­utes — soon you’ll see frost­work pat­terns ap­pear­ing on the glass!

Where do these “frost­work” pat­terns come from?

Car­bamide read­i­ly dis­solves in cold wa­ter, and does so even bet­ter in hot wa­ter. If you de­posit a small quan­ti­ty of hot car­bamide so­lu­tion on a piece of glass, it will form whim­si­cal crys­tals. Once the so­lu­tion starts to cool down on the glass, car­bamide has no choice but to crys­tal­lize as the wa­ter cools too much for all the car­bamide to stay dis­solved. Nee­dle-like crys­tals grow on the wet glass sur­face, cre­at­ing fas­ci­nat­ing, unique pat­terns. They look like real frost­work!

Make sure to wear pro­tec­tive gloves when con­duct­ing this ex­per­i­ment. The frost­work pat­tern you cre­ate is easy to re­move from the glass – sim­ply rinse it with wa­ter.

Try it