Basic chemistry quizzess.

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1.What do you call an atom that has more protons than electrons?
    A.a molecule
    B an isotope
    C.an anion
    D.a cation.




Answer:-a cation
Explane:-If an atom has more protons than electrons, it has a net positive charge. This is a cation, which you can remember because the "t" in cation resembles a "+" sign for positive.

2.A drop of food coloring spreading out in a cup of water is an example of which transport process?
  A.Diffusion
    B.Osmosis
    C.Vapor Pressure
    D.Effusion

  
Answer:-Diffusion
Explane:-Food coloring dispersing in water is an example of diffusion. Osmosis involves water, but there has to be a semipermeable membrane, too. 

3.A mole contains Avogadro's number of items. What is Avogadro's number?


A.6023
B.6.023 x 10^23
C.6.02 x 10^-23
D.3 x 10^8

Answer:-6.023x10^23
Explane:-Avogadro's number is huge! The reason chemists use 6.02 x 10^23 to define a unit is to avoid having to work with crazy-large numbers.





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