Guided virtual science experiments for Grades 6–10. Free experiments need no account.
36 experiments found
Indicators change colour in acids and bases
Use red cabbage indicator to sort everyday liquids into acids, bases and neutral substances.
Some solids dissolve, and water can dissolve only a limited amount
Stir salt, sugar and sand into water. Find out which ones dissolve, and how much salt water can hold.
Evaporation turns liquid water into vapour; condensation turns vapour back into liquid
Heat salt water until the water evaporates and leaves salt behind, and watch water vapour condense on a cold lid.
Filtration separates insoluble solids from liquids
Filter muddy water and salty water. Discover what filter paper can and cannot remove.
The state of matter depends on how particles are arranged and how fast they move
Heat and cool water and wax, and watch how their particles are arranged and how fast they move in each state.
Physical changes can be reversed; chemical changes make new substances
Heat and cool ice, wax, sugar and egg white. Find out which changes can be reversed and which make a new substance.
Heavy insoluble particles settle, so the liquid above can be poured off
Stir sand into water, let it settle, then pour off the clear water without disturbing the sand.
A magnet separates magnetic materials from non-magnetic ones
Mix sand and iron filings, then use a magnet to pull the iron out. Find out why a magnet cannot separate salt from sand.
Solids keep their shape, liquids flow and take the shape of their container, and gases spread out to fill any space
Test everyday materials for shape, flow and how they fill a container, then sort them into solids, liquids and gases.
Heat, stirring and smaller pieces make a solid dissolve faster
Race sugar cubes and granulated sugar in cold and hot water, stirred and unstirred, and time how long each takes to dissolve.
An element has one kind of atom, a compound has different atoms chemically joined in fixed amounts, and a mixture has substances mixed but not joined
Look at particle models of everyday substances, test whether they can be separated, and sort them into elements, compounds and mixtures.
Several separation methods can be combined to separate a mixture
Use dissolving, filtration and evaporation one after another to separate salt from sand and collect salt crystals.
Gas, a new solid or a colour change can show a chemical reaction
Mix kitchen substances and look for evidence that a new substance has formed: gas bubbles or a new solid.
Iron rusts when both water and oxygen are present; salt speeds it up and coatings prevent it
Leave iron nails in six test tubes with different conditions for several days and find out what rusting needs, and how paint and zinc protect iron.
Air is matter: it takes up space, can be compressed, exerts pressure and expands when heated
Push the plunger of a sealed syringe full of air, then warm and cool a flask with a balloon on its neck.
Atoms join to form molecules; a molecule of an element has one kind of atom, and a molecule of a compound has two or more kinds
Build ball-and-stick models of common substances, count their atoms, and sort them into single atoms, molecules of elements and molecules of compounds.
Burning needs fuel, oxygen and heat (the fire triangle); take away any one and the fire goes out
Cover a burning candle with jars of different sizes and time how long it burns, then put the flame out by removing oxygen, heat or fuel.
The pH scale from 0 to 14 measures how acidic or basic a solution is
Use universal indicator to measure the pH of seven household liquids, from lemon juice to limewater, and place each on the pH scale.
Metals are shiny, malleable, sonorous and good conductors; non-metals are usually dull, brittle and poor conductors, with a few exceptions
Test elements for shine, hammering, ringing and electrical conduction, then sort them into metals and non-metals.
Carbon dioxide turns limewater milky
Make carbon dioxide from marble chips and acid, then bubble it, your breath and fresh air through limewater to see which turn it milky.
Atoms are not created or destroyed in a reaction, so a balanced equation has the same number of each kind of atom on both sides
Change the numbers in front of each substance until every kind of atom is the same on both sides of the equation, watching the molecules as you go.
The number of protons decides the element; electrons fill shells 2, 8, 8; ions have unequal protons and electrons; isotopes have different numbers of neutrons
Add protons, neutrons and electrons to build atoms of the first 20 elements, arrange the electrons in shells, and make ions and isotopes.
An acid and an alkali neutralise each other to form a salt and water; at the end point the pH is 7
Add dilute sodium hydroxide drop by drop to dilute hydrochloric acid with an indicator, watch the pH change, and find the exact point of neutralisation.
Higher temperature and smaller pieces make reactions faster
Drop fizzy tablets into cold, room-temperature and warm water, and crush one. Time which reaction finishes first.
Physical properties such as solubility, miscibility, melting and conductivity can be used to identify and group substances
Test common laboratory substances with water, heat and a conductivity tester, and group them by how they behave.
Air is a mixture: about 78% nitrogen, 21% oxygen, 1% argon and a little carbon dioxide
Trap air in a tube with damp iron wool over water, watch the water rise as the iron rusts, and compare fresh air with breathed-out air.
Metals can be arranged in order of reactivity; a more reactive metal displaces a less reactive one
Put magnesium, zinc, iron and copper in dilute acid and compare the fizzing, then see which metals can push copper and zinc out of their salt solutions.
An electric current decomposes an electrolyte: positive ions go to the cathode, negative ions to the anode
Pass a low-voltage current through acidified water and copper(II) sulfate solution, collect the gases, and see copper plate onto an electrode.
Hard water contains dissolved calcium and magnesium salts that stop soap lathering
Shake soap with soft and hard water to compare lather and scum, then soften hard water by boiling and with washing soda.
Hydrocarbons contain only carbon and hydrogen; alkanes have only single bonds, alkenes have a double bond and alkynes a triple bond
Build models of hydrocarbons, test them with bromine water, learn their uses, and sort them into alkanes, alkenes and alkynes.
Ionic bonds form when a metal transfers electrons to a non-metal; covalent bonds form when non-metal atoms share electrons
Look at which elements each compound contains, model how their electrons are transferred or shared, and sort the compounds into ionic and covalent.
An acid reacts with a base to make a salt and water
React black copper oxide with warm dilute sulfuric acid, filter off the excess, and evaporate the blue solution to grow crystals of a salt.
Oxidation is gain of oxygen; reduction is loss of oxygen
Heat shiny copper in air until it turns black, then heat black copper oxide with carbon to get the copper back.
Acids react with metals and carbonates and turn blue litmus red; bases turn red litmus blue
Test dilute hydrochloric acid and sodium hydroxide solution with zinc, marble chips, litmus and phenolphthalein to discover how acids and bases behave.
Reactions can be classified by how the reactants rearrange: A + B → AB, AB → A + B, A + BC → AC + B, and AB + CD → AD + CB
Look at the pattern of each chemical equation and sort the reactions into combination, decomposition, displacement and double displacement.
Common gases can be identified by simple tests: oxygen relights a glowing splint, hydrogen pops, carbon dioxide turns limewater milky, ammonia turns red litmus blue
Collect gases from different reactions, test each with a glowing splint, a burning splint, limewater and damp litmus, and identify it.