Module 2 questions (1 Viewer)

[Wohzazz]

Well they aren't just module 2, some are from prelimanary that i should of known, please answers if you know any. These are from the past week

1. How does ions actually make electricity conduct? I need to know the atomic interaction between electron, proton etc.
2. Do people call heat produced inside a substance internal energy or heat? I was told heat was only 'outside' energy in chemistry terms.
3. Emf, voltage, voltage drop? I thought i knew this but know i'm not sure anymore. Emf= voltage right? Does voltage drop= difference in voltage from two measured point on the circuit?
When do you use each term?
4. Why isn't the concentration of metal solids counted in equilbrium reactions? I mean when you increase the volume of gas, why doesn't the concentration of solids decrease? I mean the number of atoms or compunds of the solids decreases as the area is bigger.
5. When it says a compound has been oxidised, what does it mean? I know when you say an ion has been oxidised, it has gain electrons. But for a compound, there are multiple elements and they might seperate during a reation. So how do you know that the WHOLE compound has been oxidised.
eg. 2H(2)S+ 3O(2) gives 2SO(2)+ 2H(2)O
H(2)S has been oxidised in this case.
6. Ga(2) O(3) is ionic
Br(2) O(7) is covalent
So do you work this out by testing out whether it is ionic to see if electron add to its charge, then if not, deduce its covalent. How do you distinguish? (OH this is preliminary stuff!!!)
7. [Fe(H(2)O)(6)] 3+
Write the equation for the reaction of this ion with water. Um, what kind of ion is this called. Is there a generic name for this?
8. Aquated aluminium? What does that mean. Is it a compound?
9. Iis there a convention to writing acid/base/Carbonate equation in terms of what to write first. I find my differs from the answers in terms of order.
10. Finally, for aromatic compounds, how much about it do you need to know. ATM i only know a benzene ring is C6H6. How do get to the systematic name for benzoic acid?

That was a mouthful. I look forward to any contributions

 

[abdooooo!!!]

wow... thats a lot of questions... can't be bother to read them all. a lot of them involves physics... i'll try to answer some after reading them if i can.

 

[abdooooo!!!]

Originally posted by Wohzazz
1. How does ions actually make electricity conduct? I need to know the atomic interaction between electron, proton etc.

my understanding to this is that ions are charged particles... electricity is a flow of charged particles that can either be negative or positive ions. ions are allowed to flow when dissolved so electricity therefore can be transferred.

 

[abdooooo!!!]

Originally posted by Wohzazz

2. Do people call heat produced inside a substance internal energy or heat? I was told heat was only 'outside' energy in chemistry terms.

im pretty sure its called enthalpy in a thermodynamic function of a system.

 

[abdooooo!!!]

Originally posted by Wohzazz

3. Emf, voltage, voltage drop? I thought i knew this but know i not sure anymore. Emf= voltage right? Does voltage drop= difference in voltage from two measured point on the circuit?
When do you use each term?

not sure about this one my physics is not so good... emf is electromotive force and could be thought as voltage. a voltage drop in mind is when current is passed through the wire the resistance of the circuit causes the drop from one point to another ie. V=IR. higher the resistance higher the drop from one point to another.

 

[abdooooo!!!]

Originally posted by Wohzazz

4. Why isn't the concentration of metal solids counted in equilbrium solids? I mean when you increase the volume of gas, why doesn't the concentration of solids decrease? I mean the number of atoms or compunds of the solids decreases as the area is not bigger.

huh? what the... can you explain that again? i couldn't understand it... can you give an example of what equilbrium you want to calculate. the equilbrium constant is only affected by temperature and nothing else... changes in concentration/volumn only affects the... argg can't remeber the word lol.

 

[abdooooo!!!]

Originally posted by Wohzazz

5. When it says a compound has been oxidised, what does it mean? I know when you say an ion has been oxidised, it has gain electrons. But for a compound, there are multiple elements and they might seperate during a reation. So how do you know that the WHOLE compound has been oxidised.
eg. 2H(2)S+ 3O(2) gives 2SO(2)+ 2H(2)O
H(2)S has been oxidised in this case.

it means the element has combined with or having undergone a chemical reaction with oxygen. ie the element has loss electrons in the process. im pretty sure only sulfur has been oxidised in this case because its valence has been oxidised from from -2 to +4, hence its a plus (oxidation) in valence of 6. and hydrogen has been reduced and so too with oxygen in order to balance out the charges.

 

[Wohzazz]

edit/ deleted 'not' in q 4
4/

Here's an example from Chem Context 2
2. The reaction for the production of water gas is
C(s) + H2O(g) 6 (double arrows) CO(g) + H2(g)
if the system is at equilibrium, what would be the effect of the following changes
I) the concentration of all the species if you increase the volume of the system
answer: concentrations of H2O , CO and H2 will decrease but concentration of C(s) will remain constant

 

[abdooooo!!!]

Originally posted by Wohzazz

6. Ga(2) O(3) is ionic
Br(2) O(7) is covalent
So do you work this out by testing out whether it is ionic to see if electron add to its charge, then if not, deduce its covalent. How do you distinguish? (OH this is preliminary stuff!!!)

yeah something like that... but its kinda hard... normally when a bond involves metal element it would be ionic. if not then it should be covalent or covalent lattice. ie H2O's charges add up but is it covalent or ionic?

 

[Wohzazz]

Originally posted by abdooooo!!!
im pretty sure only sulfur has been oxidised in this case because its valence has been oxidised from from -2 to +4, hence its a plus (oxidation) in valence of 6. and hydrogen has been reduced and so too with oxygen in order to balance out the charges.

so it only has to do with a compound reacting with oxygen and it can't a compound can't oxidise in the presence of other elements and compounds.

 

[Wohzazz]

Originally posted by abdooooo!!!
yeah something like that... but its kinda hard... normally when a bond involves metal element it would be ionic. if not then it should be covalent or covalent lattice. ie H2O's charges add up but is it covalent or ionic?

Ga's a semi metal isn't it? is water like covalent? that's what i always thought but don't know why

 

[abdooooo!!!]

Originally posted by Wohzazz

7. [Fe(H(2)O)(6)] 3+
Write the equation for the reaction of this ion with water. Um, what kind of ion is this called. Is there a generic name for this?

argg... can't remember... i think its called hydrates. so that case stated above would be iron hexahydrate ion or something.

 

[abdooooo!!!]

damn man... you are asking more questions while im still reading your original questions... ahh me kinda tired now

 

[Wohzazz]

Originally posted by abdooooo!!!
damn man... you are asking more questions while im still reading your original questions... ahh me kinda tired now

LOL, you don't need to answer them all. Don't want to cause fatigue in you

 

[abdooooo!!!]

Originally posted by Wohzazz

8. Aquated aluminium? What does that mean. Is it a compound?

aquated is a species loosely bound to water molecules in a aqueous medium... so its not a compound. its a state i believe.

 

[abdooooo!!!]

me was on the phone... anyways here is the last two.

Originally posted by Wohzazz

9. Iis there a convention to writing acid/base/Carbonate equation in terms of what to write first. I find my differs from the answers in terms of order.

what convention? whats the '///' stand for?

Originally posted by Wohzazz
10. Finally, for aromatic compounds, how much about it do you need to know. ATM i only know a benzene ring is C6H6. How do get to the systematic name for benzoic acid?

for hsc you don't need to know anything. what do you mean how do you get the systematic name? i think 'benzoic acid' is not actually the systematic name according to systematic of nomenclature (IUPAC).

edit: i think i misundestood your post. so you want to know the systermatic name for benzoic acid right? its something like benzenecarboxylic acid, because.... umm you have to learn the actual rules to know.

 

[Xayma]

Originally posted by Wohzazz
Ga's a semi metal isn't it? is water like covalent? that's what i always thought but don't know why

Waters covalent. It "shares" the electrons however, oxygen has a higher electronegativity then hydrogen so has the electrons closer to it.

Ionic bonding is bonding between positive and negative ions, the only thing that holds them together is the electromagnetic force between them. A metal and a non-metal will be an ionic bond. Two non-metals would be a covalent bond.

 

[abdooooo!!!]

Originally posted by Xayma
Waters covalent. It "shares" the electrons however, oxygen has a higher electronegativity then hydrogen so has the electrons closer to it.

yep. i think thats about right.

so thats why Wohzazz, that you can't just simply say that if the the valence add up so it'll be ionic. its kinda hard to determine... but mostly just follow the if metal is involved then you assume it will be ionic otherwise covalent.

 

[Wohzazz]

Originally posted by abdooooo!!!
me was on the phone... anyways here is the last two.

what convention? whats the '///' stand for?

What i mean is for an reaction, do you write
acid + base= salt + water
or base + acid = water + salt
just was wondering if there was any conventions

Originally posted by abdooooo!!!
so thats why Wohzazz, that you can't just simply say that if the the valence add up so it'll be ionic. its kinda hard to determine... but mostly just follow the if metal is involved then you assume it will be ionic otherwise covalent.

so what about the semi metal like i mentioned? do you have to add them up?
my thoughts for Ga(2) O(3), each Ga give 3 electrons (6 total) to the 3 O. therefore they add up
for Br(2) O(7), i suppose you can deduce it from Xayma's 2 non metals form covalent bonds

 

[Wohzazz]

Originally posted by abdooooo!!!
aquated is a species loosely bound to water molecules in a aqueous medium... so its not a compound. its a state i believe.

when does this state occur, is it just like Al ions in water? maybe when you have a metal oxide in an acid solution?