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  • Smart Learning for All

  • Topic: Sublimation.

  • Why do mothballs disappear over time?

  • Wow.

  • You have a nice collection of clothes.

  • But have you kept mothballs to protect them?

  • I had kept them a few months back below these clothes.

  • Hey, where did the mothballs go?

  • I had placed them right here.

  • Did you steal them?

  • No No.

  • I haven't stolen anything.

  • Mothballs disappear over time.

  • Do you know why?

  • It is because of a process called sublimation.

  • During sublimation, a solid on heating.

  • Converts directly into vapor without passing through the intermediate liquid state.

  • Don't lie.

  • How is that even possible?

  • See, I also hid a burger here many days ago.

  • It did not disappear.

  • Gross.

  • Just throw that burger in the dustbin.

  • Not all substances sublimate.

  • Mothballs are made up of naphthalene.

  • Naphthalene has very weak intermolecular forces.

  • Because of these weak forces.

  • The mothball which is made up of naphthalene sublimates.

  • It changes its state from solid to vapor.

  • Now, this vapor is either absorbed by the fabric.

  • Or it escapes into the atmosphere causing the mothballs to disappear over time.

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A2 US disappear vapor burger solid weak clothes

Sublimation - Why do mothballs disappear over time? | #aumsum

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    AumSum posted on 2019/04/18
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