A. Air expands, becomes less dense and rises when the temperature is high due to the increased kinetic energy. This causes the air molecules to move around much more so they are further apart.
Answer:
17. The iron metal is oxidized to form the iron oxide known as rust.
19.A saturated solution will not dissolve any more solute and any extra solute added will simply stay as it is, without dissolving. An unsaturated solution has less solute than its solubility and hence can still add more solute, till it reaches the saturation level.
26 An Overflowing Population. The swelling American population played a large part in the decision Americans made to head, The Government Opens Up New Land. The American government itself encouraged its citizens to move west
32. The periodic table was first assembled in 1869 by a Russian chemist named Dmitri Mendeleev. He came up with a way of organizing the elements that were known at the time, arranged them in order of atomic weight, and then grouped them into rows and columns based on their chemical and physical properties. Here is a unique "Mayan" format Periodic Table. Elements in the same group are those that are in a single vertical line from top to bottom. They have the most in common between the two directions. They share the same number of electrons in their valence subshells.
Explanation:
To be honest, I learned this in school so I'll tell you XD
The formula of sodium oxide is Na2O
Put it in a beaker. Use a smaller beaker filled half way with ice and water and place in the larger one. It should be about an inch or two above the mixture. Heat over a Bunsen burner and the naphthalene will deposit on the bottom of smaller beaker.
And in this way, nephthalene be separated from the mixture of KBR and sand.
Answer:

Explanation:
» The prediction is 98% correct because single displacement reaction type is highly possible.
This is because Fluorine has is more electronegative than Chlorine in Potassium Chloride. So, it strongly displaces Chlorine from the solution hence forming Chlorine gas.
» The 2% of wrong prediction maybe because of wrong reactant measurements following mole concept chemistry.
If you are asked the observation,
Observation » <u> </u><u>A</u><u> </u><u>green</u><u> </u><u>yellowish</u><u> </u><u>gas</u><u> </u><u>is</u><u> </u><u>formed</u><u>.</u>
This gas is Chlorine gas (Cl2)