1) Which of the following is not an element
a) Ozone b) Water c) Krypton d) Lead
I am not sure if the answer is (a) or (b), does anyone have any idea?

2) The earth's atmosphere is an example of a
a) solution b) mixture c) both (a) and (b)
The standard answer in my text book is (c), but I don't understand why...I picked (b), why is the atmosphere also a solution?

3) Why is an alloy a solid solution? Does that mean the solvent is solid? Why is it not a compound?

Can somebody explain? Thanks!

Re #2, think clouds. ;)

1) Which of the following is not an element
a) Ozone b) Water c) Krypton d) Lead
I am not sure if the answer is (a) or (b), does anyone have any idea?

2) The earth's atmosphere is an example of a
a) solution b) mixture c) both (a) and (b)
The standard answer in my text book is (c), but I don't understand why...I picked (b), why is the atmosphere also a solution?

3) Why is an alloy a solid solution? Does that mean the solvent is solid? Why is it not a compound?

Can somebody explain? Thanks!

Since you've already been given a major hint on #2 ;) , I'll take on 1 & 3.

1) - b) Water. It consists of two different elements, hydrogen and oxygen.

The solvent is a solid when it cools and so is the solute. It's a solid solution rather than a compound because NO chemical reaction has taken place.

1) So the answer is (b), but ozone is an element? It has covalent bonds though... :eek:

2) A solution is an example of a homogeneous mixture, so if the atmosphere satisfies (a)-solution, it must satisfy (b)-mixture too, and the answer is (c)-both (a) and (b)

The thing is I don't get how the atmosphere would be a solution, or a homogeneous mixture...

3) By solid solution, does it mean the solvent and the solute both are solid? So what would you call if a liquid in dissolved in a solid, is this still a solid solution? What if CO2(g) is dissolved in H2O(l)? Liquid solution?

#3 is a rather poor question. MHO. Some alloys are solid solutions. But more common are mixtures of a solid solution and various particulates and crystals. Carbon granules, intermetalic compounds, metalic carbides to name a few.

#2 many gases mix homogenously. O2 and N2 certainly do.

2) How does it differ if gases mix homogeneously or heterogenerously? What does it mean N2 and O2 mix homogeneously (i.e. solution), can you explain a bit? For what reason is the earth's atmosphere being considered as a solution/homogeneous mixture?
Thanks!

Actually, I may be a little fuzzy on the difference between homogneous and heterogeneous. You might want to check the precise definitions. What I meant about N2 and O2 is that they uniformly diffuse into each other, such that the two are intermingled right down to the level of individual molecules. In this they are more characteristic of a solution than a mixture.

1) So the answer is (b), but ozone is an element? It has covalent bonds though... :eek:

2) A solution is an example of a homogeneous mixture, so if the atmosphere satisfies (a)-solution, it must satisfy (b)-mixture too, and the answer is (c)-both (a) and (b)

The thing is I don't get how the atmosphere would be a solution, or a homogeneous mixture...

3) By solid solution, does it mean the solvent and the solute both are solid? So what would you call if a liquid in dissolved in a solid, is this still a solid solution? What if CO2(g) is dissolved in H2O(l)? Liquid solution?Ozone is considered an element because O3(g) consists of only oxygen so it is an element jsut like S8(s).The atmosphere is a solution because all the different types of molecules are everly distributed If it is talking about just a sample of air if it is talking about the whole atmosphere, then I would have to say that it is mechanical because of the Ozone layer. If a liquid is dissolved in a solid it is no longer a liquid it might have seperate into it's ions or the seperate molcules might have just disolved. The state of a solution depends on it's properties if it has a definite shape and definite volume it is a solid, if it has an indefinite shape but a definite volume it is a liquid if it has an indefinite volume and shape it is a gas but uinder most circumstances the state of the solution=the state of the solvent

2) How does it differ if gases mix homogeneously or heterogenerously? What does it mean N2 and O2 mix homogeneously (i.e. solution), can you explain a bit? For what reason is the earth's atmosphere being considered as a solution/homogeneous mixture?
Thanks!It all depends on polatity if the two substances are both polar or both nonpolar they will be homogenious. It one is polar and the other is nonpolar, they will form a mechanical mixture.

) Which of the following is not an element
a) Ozone b) Water c) Krypton d) Lead
I am not sure if the answer is (a) or (b), does anyone have any idea?

2) The earth's atmosphere is an example of a
a) solution b) mixture c) both (a) and (b)
The standard answer in my text book is (c), but I don't understand why...I picked (b), why is the atmosphere also a solution?

3) Why is an alloy a solid solution? Does that mean the solvent is solid? Why is it not a compound?

Can somebody explain? Thanks!

Answers

1- a and b. Ozone is not the same as pure Oxygen and water sure isn't

2- c, because it is a solution( contains water) and is also a mixture of gases and impurities

3- An alloy is a mixture of two or more solids, which is why it is a solid solution. But solution in chemistry usually refers to anything mixed with water. Its not a compound if its not chemicaly bonded, remember an alloy is a mixture and mixtures can be seperated by physical means more than half the time. The main reaosn why its not a compound is because they don't form new substances due to their weaker metallic bonds.