general rules for physical and chemical change

[nickh]

Hey guys,

I'm just wondering what's a good rule to decide if something's a physical or chemical change? Like I know physical change is one state to another, while chemical is when there's a reaction going on or formula changes. But what about for hydrolysis for example, or dissolving or sugar or salt.

Thanks again

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[FutureDentist121]

One might be if its a reversible reaction then its a physical change. So if something is an irreversible reaction then it should be a chemical change.

I don't think there is a foolproof method but the one I shown above should work for most of them.

 

[DAT Destroyer]

Hey guys,

I'm just wondering what's a good rule to decide if something's a physical or chemical change? Like I know physical change is one state to another, while chemical is when there's a reaction going on or formula changes. But what about for hydrolysis for example, or dissolving or sugar or salt.

Thanks again

As a general rule if you see a change of state and it does not change the identity of the substance it is a physical change; melting, boiling, freezing and the crushing of an aspirin are good examples. If the identity of the substance is changed such as in burning, tarnishing, and rusting it is a chemical change. The clotting of blood is another good example of a chemical change.

Hope this helps, keep up the great work!

 

[nickh]

Got it, thanks everyone