Answer:
Q1: Gases, liquids and solids are all made up of atoms, molecules, and/or ions, but the behaviors of these particles differ in the three phases. ... gas are well separated with no regular arrangement. liquid are close together with no regular arrangement. solid are tightly packed, usually in a regular pattern.
Q2: Mass is how much stuff something is made of. Volume is how much space an object takes up.
Ah, stoichiometry. Have you ever done ratios before?
When you are given chemical reactions, all of the moles of reactant and product are proportional. This means that they're in ratio. Say we double the number of moles of water to 12 moles. How many moles do you think C2H6 will have? It'd be 4 moles, since just like water it was doubled since they're in proportion.
You can also think about that example above like a literal ratio. Since the original ratio is 2:6, it then turns into n:12, with n being the unknown number of moles of C2H6. Since ratios we know that ratios are always equal can be converted to fraction:
2/6 = n/12
Cross multiply:
24 = 6n
n = 4 moles
Makes sense? On to the actual question.
We're looking at the proportion between oxygen and carbon dioxide. Let's write that into a ratio:
7:4
Since there are seven moles of oxygen and four moles of carbon dioxide.
The number of moles of carbon dioxide is reduced to 1 mole. You could simply divide seven by 4 to find your answer (Since 4 was divided by 4 to make 1), but let's use the ratio method just in case questions in the future aren't this convenient:
7:4 becomes n:1
Convert to fraction:
7/4 = n/1
Cross multiply;
7 = 4n
Divide:
n = 7/4
Convert to decimal:
n = 1.75
The answer is Option C, 1.75 moles.
Let me know if you want me to explain anything I did here.
Good luck!
-T.B.
Answer:
it is a replacement reaction
The given question is incomplete. the complete question is:
The electron arrangement ions
and
are 2, 8, and 2, 8, 8 respectively.
Write the electronic arrangement of the elements X and Y.
Write the formula of the compound that would be formed between X and Y.
Answer: 1. The electronic arrangement for X and Y are 2,8, 3 and 2,8,5 respectively.
The formula of the compound formed is 
Explanation:
Electronic configuration is the arangement of electrons in an atom in order of increasing energies.
Cations are formed when electrons are lost by atoms and anions are formed when electrons are gained by atoms.




For formation of a neutral ionic compound, the charges on cation and anion must be balanced.
Here element X is having an oxidation state of +3 called as
cation and
is an anion with oxidation state of -2. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral 