Water takes longer to cool down and heat up because it detains temperature longer. So in the summer, coastal areas are cooler and the in the winter, coastal ares are warmer.
Noble gases are the least reactive of all elements. That's because they have eight valence electrons, which fill their outer energy level. This is the most stable arrangement of electrons, so noble gases rarely react with other elements and form compounds.
<u>Solution</u> : Emperical Formula = 
Emperical Formula - A formula that gives the simplest whole number ratio of atom in a compound.
In the question percentages are given then assume that the total mass is 100grams so that the mass of each element is equal to the percentage given.
Given : 80.0g Carbon
20.0g Hydrogen
First convert the given masses into moles.


Value of each mole divided by the smallest number of moles and then round off.
Moles ratio of the element are


This is the mole ratio of the elements and is repersented by the subscript in the emperical formula.
Emperical Formula = 
Actual volume=Final Volume-initial volume

Now


