When the boss is away.......(CONTEST)

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some of them is solubility questions 5 of them are like this
If the solubility of silver chloride in water @ 25 degree C is 0.045 g/100 mL, a 200 mL solution @ 25 degree C containing 0.090 g of silver choloride would be
a. supersaturated & concentrated B, saturated & concentrated
c. supersaturated & dilute d. saturated & dilute
 
satire well im going to be operator at plant, so would you check my answers after i do test please, test is do next monday, so im working onthem
 
lamuscleman said:
some of them is solubility questions 5 of them are like this
If the solubility of silver chloride in water @ 25 degree C is 0.045 g/100 mL, a 200 mL solution @ 25 degree C containing 0.090 g of silver choloride would be
a. supersaturated & concentrated B, saturated & concentrated
c. supersaturated & dilute d. saturated & dilute
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0.090g AgCl / 200 ml = 0.045g AgCl / 100 ml = the solubility, thus it is saturated, and concentrated. Maximum solubility without heating the solution and supersaturating it.
 
bittter that sucks, but maybe wrong address i just checked mail and i had some x dream in mine, hehe maybe it was yours, at least you won im on top of you and came close to winning twice
 
If the solubility of sugar in water @ 25 degree C is 45 g/100mL, a 100 mL solution @ 25 degree c containing 65 g of sugar would be
A. unsaturated B saturated c supersaturated

this is unsaturated i believe because the dose got bigger,
 
lamuscleman said:
If the solubility of sugar in water @ 25 degree C is 45 g/100mL, a 100 mL solution @ 25 degree c containing 65 g of sugar would be
A. unsaturated B saturated c supersaturated

this is unsaturated i believe because the dose got bigger,
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65g sugar / 100 ml is > 45 g sugar / 100ml thus it is supersaturated.
 
satire thanks i got it now, opposite, got another question where it goes from 45g/100 ml to 25g/100 ml, that would be . a unsaturated. b saturated. c supersaturated
that would be unsaturated correct
 
bitter these are the easy questions, hard one is like this

8. A mixture of gases contains CH4, C2H6, and C3H8. If the total pressure of the mixture is 1.50 atm and the container contains 0.5 mole CH4, 0.70 mole C2H6, and 0.25 mole C3H8, what is the partial pressure of C3H8 in the mixture?
 
bitter its hard bc he left for 1 and half week and we have to train ourselves this and its summer session so its like 3 week of regular classes
 
lamuscleman said:
bitter these are the easy questions, hard one is like this

8. A mixture of gases contains CH4, C2H6, and C3H8. If the total pressure of the mixture is 1.50 atm and the container contains 0.5 mole CH4, 0.70 mole C2H6, and 0.25 mole C3H8, what is the partial pressure of C3H8 in the mixture?
Click to expand...

.2586 atm is my calculation
 
i just dont know how to set up the problems, what to add, stuff like that, i guess i will go to my old school and see if i can get help from chemistry tutor bc i want to make an a
 
lamuscleman said:
i just dont know how to set up the problems, what to add, stuff like that, i guess i will go to my old school and see if i can get help from chemistry tutor bc i want to make an a
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Dude, just look at the units and work it out that way. You know what you're putting in, what you want out. Just work all your problems with the units included and do math on the units. It's simple algebra. I never memorize any equations as in physics there's a billion. We just work out the units to figure out the problem.
 
lamuscleman said:
bitter these are the easy questions, hard one is like this

8. A mixture of gases contains CH4, C2H6, and C3H8. If the total pressure of the mixture is 1.50 atm and the container contains 0.5 mole CH4, 0.70 mole C2H6, and 0.25 mole C3H8, what is the partial pressure of C3H8 in the mixture?
Click to expand...

There should be an answer for .375 if it's multiple-guess. Why would various gas's be at uneven pressures in a gaseous state? They all disperse evenly.

Dude I'm going to feel bad if you die in a fire at a fuel plant because you can't do these correctly!
 
SatireWolf said:
There should be an answer for .375 if it's multiple-guess. Why would various gas's be at uneven pressures in a gaseous state? They all disperse evenly.

Dude I'm going to feel bad if you die in a fire at a fuel plant because you can't do these correctly!
Click to expand...

But of course that's a trick :)
 
lamuscleman said:
bitter these are the easy questions, hard one is like this

8. A mixture of gases contains CH4, C2H6, and C3H8. If the total pressure of the mixture is 1.50 atm and the container contains 0.5 mole CH4, 0.70 mole C2H6, and 0.25 mole C3H8, what is the partial pressure of C3H8 in the mixture?
Click to expand...

The real answer is:

total moles = 0.5 + 0.70 + 0.25 = 1.5 in chemistry rounding, because you can't add precision.

ie... it's actually 0.5 + 0.7 + 0.3. Always round up.

So it's actually.... 0.25/1.5 = 0.1666666 rounded up 0.17 * 1.5 atm = 0.255 or 0.26 not increasing precision.
 
ok well bitter said .2586 atm, so it seems close, there is no answer for these its fill inthe blank, at oil refinary , i wouldnt be doing any calculations thats for enginners, but im trying to learnhow to do it, it doesnt hurt
 
lamuscleman said:
satire the process technicians do not do this, the chemical engineers do this
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so in all the processing, and cracking you never have to figure out the pressure, temperature, or density of anything??? I think you're mistaken sir. Refineries are nothing but pressure, density, and temperature....

My uncle is a head engineer for shell, goes all over the world fixing process problems at plants. They all come down to the basics...
 
lamuscleman said:
ok well bitter said .2586 atm, so it seems close, there is no answer for these its fill inthe blank, at oil refinary , i wouldnt be doing any calculations thats for enginners, but im trying to learnhow to do it, it doesnt hurt
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You can't increase precision, he'll count it wrong. Or at least subtract points. If you have 0.5 moles your end answer should have 1 significant figure.... Or did ya'll not cover that?
 
satire, the outside operators do not have to do this, they have standard set points for these set by engineers, and the inside operators tell the outside operators what to do, but i understand what your saying, we get samples and give it to engineers and we have to raise the temperature to make it more pure and such
 
we covered that i made 100 on that test, i know how to do moles and such, and this test doesnt look to hard, im just freaking out because he said no one made an A and im trying to make one so im not focusing
 
lamuscleman said:
satire, the outside operators do not have to do this, they have standard set points for these set by engineers, and the inside operators tell the outside operators what to do, but i understand what your saying, we get samples and give it to engineers and we have to raise the temperature to make it more pure and such
Click to expand...

cracking is a delicate partial pressures problem, combined with fluid mechanics that gets a bit more complicated, but the end result is one big density/pressure/temperature problem.
 
and i know some reactants cant take place depening on the chemical its being reactaed with , so im trying to look for the trick hard questions.
 
satire yes i understand im taking fluid mechanics class next semester for my last semester, and they said this class is easy , the chem teacher is mad bc he said this needs to bethe hardiest class at my school but they made it easy, most students dont pay attention they think they wont need it, im trying to learn as much as possible
 
SatireWolf said:
The real answer is:

total moles = 0.5 + 0.70 + 0.25 = 1.5 in chemistry rounding, because you can't add precision.

ie... it's actually 0.5 + 0.7 + 0.3. Always round up.

So it's actually.... 0.25/1.5 = 0.1666666 rounded up 0.17 * 1.5 atm = 0.255 or 0.26 not increasing precision.
Click to expand...

I forgot all about the precision stuff. Good catch!
 
SatireWolf said:
You can't increase precision, he'll count it wrong. Or at least subtract points. If you have 0.5 moles your end answer should have 1 significant figure.... Or did ya'll not cover that?
Click to expand...

This is the correct way to do things, and the teacher should take off if you don't do the significant digits the right way.
 
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