Salt Dissolving in Water

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905373636
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Joined: Thu Aug 01, 2019 12:15 am

Salt Dissolving in Water

Postby 905373636 » Thu Jan 09, 2020 4:11 pm

This is a question that has haunted me for many years:

Is salt (NaCl) dissolving in water a physical or chemical change?

In water the ions are technically separated as the sheer [H2O] is powerful enough to separate them (the amount of ion-dipole interactions is more and stronger than the ionic bonds) and thus I'd say the composition of salt changes and it's thus a chemical change.

However, when the salty water evaporates, salt crystals form once again on the bottom of the container.

Sugar dissolving in water is a physical change as the molecule doesn't separate in water, but salt does. However, both form crystals at the bottom of their containers when the water is evaporated.

What do y'all think?

Tai Metzger 3K
Posts: 103
Joined: Sat Aug 24, 2019 12:17 am

Re: Salt Dissolving in Water

Postby Tai Metzger 3K » Thu Jan 09, 2020 4:22 pm

I hope I can help you resolve this haunting question. I believe that it is a physical reaction because no bonds are broken.

905373636
Posts: 62
Joined: Thu Aug 01, 2019 12:15 am

Re: Salt Dissolving in Water

Postby 905373636 » Mon Jan 13, 2020 12:21 pm

Tai Metzger 3K wrote:I hope I can help you resolve this haunting question. I believe that it is a physical reaction because no bonds are broken.


I thought, though, that salt dissolving in water meant that the ions bonds were broken -- making the solution homogeneous (?)

Joseph Saba
Posts: 154
Joined: Thu Jul 11, 2019 12:16 am

Re: Salt Dissolving in Water

Postby Joseph Saba » Mon Jan 13, 2020 12:28 pm

I think its a physical change. But I also think you should see someone about this nightmare.


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