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#1
Hey guys, I have a chem test tomorrow, and I wonder if anyone here is any good at it, because I have some questions and stuff


How many electrons are used in the carbon-carbon bond in C2H2?
A) 2
B) 4
C) 6
D) None


Arrange the following molecules in decreasing bond polarity
Cl2 HF H2O
A) Cl2 > HF > H2O
B) HF > Cl2 > H2O
C) HF > H2O > Cl2
D) H2O > HF > Cl2
E) H2O > Cl2 > HF


Which statement best describes electronegativity?
A) The negative charge of an non-metal ion
B) The tendency of an atom in a molecule to change the electron configuration of itself.
C) The tendency of an atom in a molecule to pull the protons of another atom away from itself.
D) The tendency of an atom in a molecule to attract a pair of shared electrons towards itself.


Water is a dipole but carbon dioxide (CO2) is not. Why?
A) No polar covalent bonds are present in carbon dioxide
B) Carbon dioxide has a linear shape whether water has a bent shape.
C) Water has a linear shape whether carbon dioxide has a bent shape.
D) The bond polarity are weaker within carbon dioxide compare to water.


Sodium chloride can easily be dissolved in water. Which type of interparticle attraction is dominating in the solution?
A) Ion - dipole attraction
B) Dipole - dipole attraction
C) van der Waals forces
D) Covalent bonding


Methanol (CH3OH) doesn´t dissolve in petroleum but butanol (C4H9OH) does. How come?
A) Methanol is an ionic compound and butanol is a molecule
B) Methanol has a dominating polar group whether butanol has a dominating non-polar part.
C) Methanol is a non-polar molecule and butanol is a polar molecule.
D) Petroleum and butanol are solids but methanol are a liquid.


How can you determine if a solution of CaCl2 is saturated?
A) Add more CaCl2; if it doesn´t dissolve, it is saturated
B) Add more CaCl2; if it dissolve, it is saturated
C) Heat the solution to see if there is a precipitate forming
D) As long as there are more water molecules than calcium and chloride ions, there is a saturated solution


Which interparticle attractions exist between molecules of carbon monoxide, CO?
A. Ion-dipole atttractions
B. Dipole-dipole attractions
C. Van der Waals’ forces
D. Hydrogen bonding


Moles and number of molecules
Calculate the amount of substance (the number of moles) in 9,632 x 1023 molecules HCl. Remember the unit!

10,7 g of saccharose is added to 125 cm3 water. What is the final concentration of saccharose in the solution? Remember unit please!


An original salt solution has the concentration 0,5 mol/dm3. You need 200 ml of a diluted version of the solution. The diluted concentration is 0,2 mol/dm3. Which volume of the original solution do you need to make the new solution? Give your answer in ml!
Quote by luxeion
i keep asking my dad for wood. but he keeps getting annoyed (he's working on a house). and i'm too young to go outside.

Last edited by StrykVladzimsky at Mar 13, 2012,
#2
Good chemistry is important. A relationship based on sex alone usually ends pretty quickly.
#4
In Hydrogen Chlorine, (HCl) 2 electrons are used in the bond, right?
Quote by luxeion
i keep asking my dad for wood. but he keeps getting annoyed (he's working on a house). and i'm too young to go outside.

#6
Cool, I can't get my head around it..
Quote by luxeion
i keep asking my dad for wood. but he keeps getting annoyed (he's working on a house). and i'm too young to go outside.

#8
4th year pharmaceutical and biomedical chemist and funding dependent il be doing a phd designing an anticancer drug so yes i know a little bit of chem
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#10
I have the choice of 2,4,6 or none. I think it's 2 because they both join up and two are involved, but I don't know.
Quote by luxeion
i keep asking my dad for wood. but he keeps getting annoyed (he's working on a house). and i'm too young to go outside.

#11
I'm pretty sure that it depends on the molarity. Are the bonds sub- or base level?
#12
A chemical bond is a PAIR of electrons. So 2.
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#13
1 electron, cause H+ and Cl-
check your periodical table if you wanna know
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#14
I don't know, but it's really only a tenth grade test, so I doubt it's that advanced.
Quote by luxeion
i keep asking my dad for wood. but he keeps getting annoyed (he's working on a house). and i'm too young to go outside.

#15
Beef- It's what I thought then..
Quote by luxeion
i keep asking my dad for wood. but he keeps getting annoyed (he's working on a house). and i'm too young to go outside.

#16
One of the following compounds is NOT a molecule. Which?
A) Ethanol
B) Nitrogen dioxide
C) Hydrogen chloride
D) Barium chloride
E) Metanol

There's another one..
Quote by luxeion
i keep asking my dad for wood. but he keeps getting annoyed (he's working on a house). and i'm too young to go outside.

#17
Quote by StrykVladzimsky
Beef- It's what I thought then..


Yep.

Quote by StrykVladzimsky
One of the following compounds is NOT a molecule. Which?
A) Ethanol
B) Nitrogen dioxide
C) Hydrogen chloride
D) Barium chloride
E) Metanol

There's another one..


E, because it's a spelling error. "Methanol" is what I'm assuming it's supposed to be.

Also; just post all your questions in the OP and save yourself this hassle, and make it easier to read.
I shall grant you three wishes.

None of which will work.


Does the above post enrage, offend or confuse you?

Good.


I like my women how I like my guitars. Curvy and like it when I finger them.
Last edited by BeefWellington at Mar 13, 2012,
#18
Quote by nemesisarmy
1 electron, cause H+ and Cl-
check your periodical table if you wanna know


It's HCL2, so it's two.
...Stapling helium to penguins since 1949.
#19
first question: they share one pair of electrons (so 2 electrons)
second question: I'd say all of them are molecules
#20
Beef, my Chem teach is Swedish and english ain't his first language, so it's not the language I assume.
Quote by luxeion
i keep asking my dad for wood. but he keeps getting annoyed (he's working on a house). and i'm too young to go outside.

#21
Quote by StrykVladzimsky
I have the choice of 2,4,6 or none. I think it's 2 because they both join up and two are involved, but I don't know.

It has two since it's a covalent bond and 2 electrons are shared between them.
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#22
From the list you provided, all options are molecules.

Molecule: A group of atoms bonded together.
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#23
I know that, but why would there even be a question like that then? pure confusion?
Quote by luxeion
i keep asking my dad for wood. but he keeps getting annoyed (he's working on a house). and i'm too young to go outside.

#25
Quote by StrykVladzimsky
I know that, but why would there even be a question like that then? pure confusion?

There surely is a "none of the above" option? If not.. you need to talk with your teacher.
Quote by Trowzaa
I wish I was American.

~ A Rolling Potato Gathers No Moss ~
#26
Quote by StrykVladzimsky
Beef, my Chem teach is Swedish and english ain't his first language, so it's not the language I assume.


If he's put the spelling error in there intentionally (which he must have done), it's E. If he hasn't, and he means "methanol", then it's a trick question. I can only assume he must have put "metanol" intentionally.
I shall grant you three wishes.

None of which will work.


Does the above post enrage, offend or confuse you?

Good.


I like my women how I like my guitars. Curvy and like it when I finger them.
#27
Quote by eGraham
There surely is a "none of the above" option? If not.. you need to talk with your teacher.


As I said, he's Swedish, and his English ain't great. I am going to have to.
Quote by luxeion
i keep asking my dad for wood. but he keeps getting annoyed (he's working on a house). and i'm too young to go outside.

#28
following the order of the questions since your edit:

electrons in carbon-carbon bond - 6 electrons, I'm sure of it

polarity question - I'm not sure, I think you need to see a table of polarity values.

electronegativity question - I think its this one D) The tendency of an atom in a molecule to attract a pair of shared electrons towards itself.

dipole question - I'd say this one B) Carbon dioxide has a linear shape whether water has a bent shape.

sodium chloride - B) Dipole - dipole attraction, though i'm not sure

methanol and butanol question - I should know that, but I really don't

How can you determine if a solution of CaCl2 is saturated?
A) Add more CaCl2; if it doesn´t dissolve, it is saturated

carbon monoxide question: I'm not sure but I'd say A. Ion-dipole atttractions

the other exercise I don't feel like doing it

hope that helped
Last edited by little_boy at Mar 13, 2012,
#29
First one is 6. Octet rule.

I don't want to do the rest because I'm a biologist and chemistry scares me.
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#30
The one with petrol is B. Longer hydrocarbons tend to be much less polar than shorter ones of the same sort. Methanol has one carbon whereas buthanol has four.

Forgive my insufficient chemistry related vocabulary in English.
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#31
Thank you so much! I go IB program, and everything is weird because it should be in English (I'm an American studying in Sweden) But some Swedes English ain't that great.
Quote by luxeion
i keep asking my dad for wood. but he keeps getting annoyed (he's working on a house). and i'm too young to go outside.

#33
Quote by StrykVladzimsky
Hey guys, I have a chem test tomorrow, and I wonder if anyone here is any good at it, because I have some questions and stuff


How many electrons are used in the carbon-carbon bond in C2H2?
C) 6


Arrange the following molecules in decreasing bond polarity
Cl2 HF H2O
C) HF > H2O > Cl2
I think, can't be bothered to find that atom chart..


Which statement best describes electronegativity?
D) The tendency of an atom in a molecule to attract a pair of shared electrons towards itself.


Water is a dipole but carbon dioxide (CO2) is not. Why?
B) CO2 has a linear shape H20 doesn't


Sodium chloride can easily be dissolved in water. Which type of interparticle attraction is dominating in the solution?
A) Ion - dipole attraction
B) Dipole - dipole attraction
C) van der Waals forces
D) Covalent bonding
Don't remember and reading this stuff in English makes my brain hurt.


Methanol (CH3OH) doesn´t dissolve in petroleum but butanol (C4H9OH) does. How come?
B) Methanol has a dominating polar group whether butanol has a dominating non-polar part.


How can you determine if a solution of CaCl2 is saturated?
A) Add more CaCl2; if it doesn´t dissolve, it is saturated
So you didn't get that one? Really?
inb4 do your own homework


Which interparticle attractions exist between molecules of carbon monoxide, CO?
A. Ion-dipole atttractions
B. Dipole-dipole attractions
C. Van der Waals’ forces
D. Hydrogen bonding
Don't remember plus dunno what these things are in Swedish so...


Not gonna be doing those last ones, requires calculators and shit which is too much effort from this pit monkey


Good luck in life.
You'll Never Walk Alone!
#34
Quote by Sir Daniel
I don't want to do the rest because I'm a biologist and chemistry scares me.

It scares everyone
#35
Hahaha
Quote by luxeion
i keep asking my dad for wood. but he keeps getting annoyed (he's working on a house). and i'm too young to go outside.

#36
Quote by little_boy
It scares everyone


Phsyics = Relatively simple
Biology=Damn simple
Chemistry =HOLYHELLWTF??
Quote by luxeion
i keep asking my dad for wood. but he keeps getting annoyed (he's working on a house). and i'm too young to go outside.

#38
Quote by StrykVladzimsky
Phsyics = Relatively simple
Biology=Damn simple
Chemistry =HOLYHELLWTF??

me at chemistry classes

#39
I appear to have blacked out or something for like the past month during chem.

EDIT: It's good to know I'm not the only one who's this bad at chem.
Quote by luxeion
i keep asking my dad for wood. but he keeps getting annoyed (he's working on a house). and i'm too young to go outside.

Last edited by StrykVladzimsky at Mar 13, 2012,
#40
Quote by StrykVladzimsky
Hey guys, I have a chem test tomorrow, and I wonder if anyone here is any good at it, because I have some questions and stuff


How many electrons are used in the carbon-carbon bond in C2H2?
A) 2
B) 4
C) 6
D) None


Arrange the following molecules in decreasing bond polarity
Cl2 HF H2O
A) Cl2 > HF > H2O
B) HF > Cl2 > H2O
C) HF > H2O > Cl2
D) H2O > HF > Cl2
E) H2O > Cl2 > HF


Which statement best describes electronegativity?
A) The negative charge of an non-metal ion
B) The tendency of an atom in a molecule to change the electron configuration of itself.
C) The tendency of an atom in a molecule to pull the protons of another atom away from itself.
D) The tendency of an atom in a molecule to attract a pair of shared electrons towards itself.


Water is a dipole but carbon dioxide (CO2) is not. Why?
A) No polar covalent bonds are present in carbon dioxide
B) Carbon dioxide has a linear shape whether water has a bent shape.
C) Water has a linear shape whether carbon dioxide has a bent shape.
D) The bond polarity are weaker within carbon dioxide compare to water.


Sodium chloride can easily be dissolved in water. Which type of interparticle attraction is dominating in the solution?
A) Ion - dipole attraction
B) Dipole - dipole attraction
C) van der Waals forces
D) Covalent bonding


Methanol (CH3OH) doesn´t dissolve in petroleum but butanol (C4H9OH) does. How come?
A) Methanol is an ionic compound and butanol is a molecule
B) Methanol has a dominating polar group whether butanol has a dominating non-polar part.
C) Methanol is a non-polar molecule and butanol is a polar molecule.
D) Petroleum and butanol are solids but methanol are a liquid.


How can you determine if a solution of CaCl2 is saturated?
A) Add more CaCl2; if it doesn´t dissolve, it is saturated
B) Add more CaCl2; if it dissolve, it is saturated
C) Heat the solution to see if there is a precipitate forming
D) As long as there are more water molecules than calcium and chloride ions, there is a saturated solution


Which interparticle attractions exist between molecules of carbon monoxide, CO?
A. Ion-dipole atttractions
B. Dipole-dipole attractions
C. Van der Waals’ forces
D. Hydrogen bonding


Moles and number of molecules
Calculate the amount of substance (the number of moles) in 9,632 x 1023 molecules HCl. Remember the unit!

10,7 g of saccharose is added to 125 cm3 water. What is the final concentration of saccharose in the solution? Remember unit please!


An original salt solution has the concentration 0,5 mol/dm3. You need 200 ml of a diluted version of the solution. The diluted concentration is 0,2 mol/dm3. Which volume of the original solution do you need to make the new solution? Give your answer in ml!


1. C) C2H2 is ethyne, which has a carbon-carbon triple bond.
2. C) HF has an ionic bond, H20 has a polar covalent bond, and Cl2 has a non-polar covalent bond.
3. D) Its practically the definition of electronegativity.
4. A) Dipole moments develop when there is bond polarity.
5. NaCl exists as Na+ and Cl- in solution.
6. Unsure. I don't know whether petroleum is a polar or non-polar solvent since it really isn't a compound. It's a mixture of undefined components.
7. A)
8. Probably B)

I'm not going to help you with the calculative ones. Those are purely application of formulae. Just go through your notes or a textbook and try them again. If you still don't get it in a day, post again in here and I'll post the answers. Also, use the Math/Science help thread.
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