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Easy Chemistry Quiz

Here is an easy and fun quiz on basic Chemistry.

Test your knowledge on phases of matter, the elements, and basic Chemistry facts. Do you know what the heaviest element is? Or what the most abundant element is in the whole universe? Have fun with this quiz and share your score!

Enjoy!

  • What does water do as it freezes?

    • Expands
    • Contracts
  • The most abundant element in the universe is…

    • Hydrogen
    • Helium
  • What is dry ice made of?

    • H2O Water
    • CO2 Carbon Dioxide
  • What color is liquid oxygen?

    • White
    • Blue
  • Elements are distinguished by number of …

    • Protons
    • Neutrons
  • Glass is a…

    • Solid
    • Liquid
  • Plasma is a…

    • Phase of matter
    • Element
  • The heaviest natural element is…

    • Iron
    • Uranium

What do you think?

19 points
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Written by riverwild

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32 Comments

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  1. I got 8/8 correct, because I remember in school being taught that glass was a liquid. I never understood it then, and since then like Indexer and Norman pointed out the fact that it is a liquid has been debunked. It is a liquid when melted, a solid when formed.

    • “A liquid has viscosity, a measure of its resistance to flow. The viscosity of water at room temperature is about 0.01 poises. A thick oil might have a viscosity of about 1.0 poise. As a liquid is cooled its viscosity normally increases, but viscosity also has a tendency to prevent crystallisation. Usually when a liquid is cooled to below its melting point, crystals form and it solidifies; but sometimes it can become supercooled and remain liquid below its melting point because there are no nucleation sites to initiate the crystallisation. If the viscosity rises enough as it is cooled further, it may never crystallise. The viscosity rises rapidly and continuously, forming a thick syrup and eventually an amorphous solid. The molecules then have a disordered arrangement, but sufficient cohesion to maintain some rigidity. In this state it is often called an amorphous solid or glass.

      molecular arrangement in a glass

      Some people claim that glass is actually a supercooled liquid because there is no first order phase transition as it cools. In fact, there is a second order transition between the supercooled liquid state and the glass state, so a distinction can still be drawn. The transition is not as dramatic as the phase change that takes you from liquid to crystalline solids. There is no discontinuous change of density and no latent heat of fusion. The transition can be detected as a marked change in the thermal expansivity and heat capacity of the material.

      The temperature at which the glass transition takes place can vary according to how slowly the material cools. If it cools slowly it has longer to relax, the transition occurs at a lower temperature and the glass formed is more dense. If it cools very slowly it will crystallise, so there is a minimum limit to the glass transition temperature.

      Density as a function of temperature
      in the phases of glassy materials

      A liquid to crystal transition is a thermodynamic one; i.e. the crystal is energetically more favourable than the liquid when below the melting point. The glass transition is purely kinetic: i.e. the disordered glassy state does not have enough kinetic energy to overcome the potential energy barriers required for movement of the molecules past one another. The molecules of the glass take on a fixed but disordered arrangement. Glasses and supercooled liquids are both metastable phases rather than true thermodynamic phases like crystalline solids. In principle, a glass could undergo a spontaneous transition to a crystalline solid at any time. Sometimes old glass devitrifies in this way if it has impurities.

      The situation at the level of molecular physics can be summarised by saying that there are three main types of molecular arrangement:

      crystalline solids: molecules are ordered in a regular lattice
      fluids: molecules are disordered and are not rigidly bound.
      glasses: molecules are disordered but are rigidly bound.
      [Just to illustrate that no such classification could ever be complete, recently scientists have succeeded in making quasi-crystals that are quasi-periodic. They do not fit into the above scheme and are sometimes described as being halfway between crystals and glass.]

      It would be convenient if we could conclude that glassy materials changed from being a supercooled liquid to an amorphous solid at the glass transition, but this is very difficult to justify. Polymerised materials such as rubber show a clear glass transition at low temperatures but are normally considered to be solid in both the glass and rubber conditions.

      It is sometimes said that glass is therefore neither a liquid nor a solid. It has a distinctly different structure with properties of both liquids and solids. Not everyone agrees with this terminology.”

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