When matter loses heat, one of the following happens:
Liquid changes to solid (freezing), or
Gas changes to liquid (condensation), or
Gas changes to solid (deposition)
1- Freezing: when the temperature of a liquid matter drops below its freezing point, the liquid usually solidifies forming crystals. Example of this is when water changes to ice
2- Condensation: when the temperature of gas is reduced, the molecules slow down and come together changing the matter into liquid. Example of this is when water vapor condenses into water droplets.
3- Deposition: Sometimes when the temperature of a gas drops, it solidifies directly without passing through the liquid phase. An example of this is when water vapor changes directly to ice in sub-freezing areas without passing through the liquid phase. This is the process through which clouds are formed.
The diagram below shows these three changes in matter.
The first answer is C, condensation is a physical process and the others are chemical.
The second answer is B, it doesn't change depending on location (the answer you chose)
The third answer is A.
The fourth answer is B. Temperature is an intensive property.
No explanations for the ones you got correct.
Answer:

Explanation:
Carbon disulphide is the liquid that can be used to separate iron fillings and sulphur powder.
When carbon disulphide is poured into the dish, the sulphur powder gets easily dissolved in the carbon disulfide. The iron fillings are left to settle on the bottom of the dish.
The iron fillings can get seperated through filtration. When the mixture of sulphur powder and carbon disulphide gets completely evaporated, the sulphur powder is left over.
Answer:
Approximately
.
Explanation:
Note that both figures in the question come with four significant figures. Therefore, the answer should also be rounded to four significant figures. Intermediate results should have more significant figures than that.
<h3>Formula mass of strontium hydroxide</h3>
Look up the relative atomic mass of
,
, and
on a modern periodic table. Keep at least four significant figures in each of these atomic mass data.
Calculate the formula mass of
:
.
<h3>Number of moles of strontium hydroxide in the solution</h3>
means that each mole of
formula units have a mass of
.
The question states that there are
of
in this solution.
How many moles of
formula units would that be?
.
<h3>Molarity of this strontium hydroxide solution</h3>
There are
of
formula units in this
solution. Convert the unit of volume to liter:
.
The molarity of a solution measures its molar concentration. For this solution:
.
(Rounded to four significant figures.)