Topic

Chemistry & materials

Mixing, states, crystals, fire — why stuff changes.

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📖 storybook Why does ice float? waterdensitystates of matterice Discover If you dissolve a whole sugar cube in water, does the water weigh more? dissolvingmassconservation Discover Why does hot cocoa mix in fast but cold milk leaves clumps? dissolvingheatspeed Discover Can you keep stirring sugar into water forever? dissolvingsaturationlimits Discover Why does a metal spoon feel colder than a wooden one sitting right next to it? heatmaterialsconduction Discover Why does sugar vanish in water but sand just sits there? dissolvingwaterstates of matter Discover Why does an iron nail turn orange and crumbly but a gold ring never does? rustmetalsoxygen Discover Why does lemon juice fizz on baking soda but water just sits there? acidsbasesreactions Discover 📖 storybook Why does soap wash off greasy hands but water alone just rolls off the grease? soapwatermolecules Discover 📖 storybook Why does a candle flame die under a glass but burn forever in the open? fireoxygencombustion Discover 📖 storybook Why do crystals have flat sides? crystalsshapesdissolving Discover Why does oil and vinegar split apart no matter how hard you shake them? mixingoilwater Discover Why does white glue dry hard but stay gooey in the bottle? gluedryingstates of matter Discover Why does red cabbage juice turn pink in lemon and green in soap? acidsbasesindicators Discover Why does a cut apple turn brown — and can you stop it? oxygenreactionsrust Discover Why does freezer ice turn out cloudy but fancy ice is crystal clear? freezingcrystalsstates of matter Discover Why does salt melt the ice on a sidewalk but sugar barely helps? dissolvingfreezingstates of matter Discover Why does hand sanitizer feel freezing cold but water doesn't? evaporationheatstates of matter Discover 📖 storybook Can stacked liquids catch an object that sinks in water? densityliquidsfloating Discover 📖 storybook How do temperature and surface area work together to change fizz speed? chemistryreactionstemperaturesurface area Discover 📖 storybook Why can a safe sealed process become warmer or cooler? chemistryreactionsheatenergy Discover 📖 storybook How can soap change the pull across a water surface? surface tensionwatersoap Discover 📖 storybook Why can cornstarch goo feel solid and liquid? materialsnon-newtonianstates of matterspeed Discover 📖 storybook What happens to a birthday candle's smoke right after you blow it out? firecandlesfuelchemistry Discover