If all they gave me was the volume of a solution, and the mass, and they want to know the density..do I just do D=M/V ?
IE
Volume = 8.11 mL
Mass 14.326 grams

We just went over this in a lecture, but it always included the mass of the cylinder

Super hi task

super proalbay

fag

is the question about chemistry, or just asking the density of a solution

It's chem, but it's super basic and I wana get a good grade(1st one) so I guess just chem, but really just density.

Also ISO Pro tips on converting shit, I hate that.

well yes, the specs of the container have nothing to do with the density of whats inside it, unless its a gas being compressed or something

d = m/v

converting what

Anything, I just hate it. Like when you gota convert it to/from 6 different measurements.

Anything, I just hate it. Like when you gota convert it to/from 6 different measurements.

read a fucking book you piece of shit

super ty.

Is the density of 1.00 L of water greater than, less than or squal to the density of 1.00 quart of water? Explain your answer (1 qt = .9464 L).

Short answer is it's equal to, gona look it up to make sure it's right.
I'd think it's equal to b/c it's the same substance, only more or less.

Or

The 1 L is more dense b/c there's more of it.
Donno, brb.

dimensional analysis is good as long as you have a grasp of the change in order of magnitude as you convert

Found this:

"The density of pure water is a constant at a particular temperature, and does not depend on the size of the sample. That is, it is an intensive property. The density of water varies with temperature and impurities."

So it's the same

Also note it does not give a temp, so I assume it's the same temp.

ya, density of a substance is the same no matter how much of it you have

unless you are talking compressing amounts of the substance into different sizes of containers, which would leave mass constant but have a different volume, so density would be different

Nope, just Chem 1211k intro class.

t4t

you will get to gases and shit in intro chem, thats the only chem ive had

Ya, just ment haven't got into it yet.

i can help you with whatever else in the course probably too, all the real chem nerds here took these classes years ago and either complicate it too much or dont remember the useless intro chem assignments

Super t4t.
I hope I won't need much/any but will take you up on said offer.

for problems like these you can rationalize always by checking the units of the answer and the units of the given quantities. so you know density is in units of g/mL (or g/cm^3) and you know 1 mL = 1 cm^3. since mass is in g and volume is in mL already, you dont even have to convert any units. just divide mass/volume and you have your density

water at the same temperature is mostly approximated as the same density no matter what the volume is. density of fluids traditionally dont change, because even though pressure pushing on them may increase, liquids are thought to be incompressible

Ty Evan


N help /w

Compound formulas

Ex
What is the formula of the compound formed between the ions SO32- and Na+?

How do I do that?
Feedback from the example

Feedback:
In the formula for a neutral ionic compound, the charges on the ions are understood, but not written.

The formula is written with the symbol of the cation (+ ion) before the symbol of the anion (- ion). The number of each type of ion in the formula, indicated with a subscript, is the minimum required to give a neutral compound. A subscript of 1 is not written, but understood.

If there is more than one of the same polyatomic ion in the formula, the symbol for the ion is enclosed in parentheses to indicate that the following subscript applies to all of the atoms in the ion.

In a neutral compound, the sum of all of the charges must be zero.

The charge on the Na+ ion = +1 and the charge on the SO32- ion = -2
so for a neutral compound the following are combined:

2 Na+ + 1 SO32- Na2SO3

where 2(+1) + 1(-2) = 0

Ty Evan


N help /w

Compound formulas

Ex
What is the formula of the compound formed between the ions SO32- and Na+?

How do I do that?
Feedback from the example

Feedback:
In the formula for a neutral ionic compound, the charges on the ions are understood, but not written.

The formula is written with the symbol of the cation (+ ion) before the symbol of the anion (- ion). The number of each type of ion in the formula, indicated with a subscript, is the minimum required to give a neutral compound. A subscript of 1 is not written, but understood.

If there is more than one of the same polyatomic ion in the formula, the symbol for the ion is enclosed in parentheses to indicate that the following subscript applies to all of the atoms in the ion.

In a neutral compound, the sum of all of the charges must be zero.

The charge on the Na+ ion = +1 and the charge on the SO32- ion = -2
so for a neutral compound the following are combined:

2 Na+ + 1 SO32- Na2SO3

where 2(+1) + 1(-2) = 0

nvm I figured it out, just dont understand it

to determine charges on compounds, there are some that are definite that you can look up, and some that you have to tell from what they are a compound with

a few examples of known oxidation numbers
hydrogen is 1
oxygen is -2

so if youve got some best friend compound like

H X O2

where x is some element that you dont know the charge of

H = 1, X = ??, 02 = -4

so, X = 3 for the compound to be neutral

This post has been edited by randomtask on Sat - Jan 23 2010 - 19:07:54

The density wouldn't change, because water is virtually incompressible for one, and for two they never even say that the pressures aren't equal.

Yeah, I like this guy's answer. Maybe I won't kill him when I start my new world order.

t4i

I got 11 OWL things left, yay.

N some help /w Mole/number calculations

EX:
How many ATOMS of sulfur are present in 3.61 moles of sulfur hexafluoride ?

How do you know how many atoms are in Sulfur? Just gota look it up or know it?

Wait nvm for the first question
1 atom in the Sulfur
SF6(sub)

nvm figured it out all together

avogadros number

6.022 x 10^23 atoms in one mole, of anything

sry i didnt help a lot m8. try IMing me.

wuts your aim again?
Blackjack21?

I should just rename this topic Johns Chem 101 help

evanpl88

this

meant to bold the chem nerds making it to complicated for what you want to do

i dont think i over-complicated anything

Substance X jas 13 protons, 14 neutrons, 10 electons.

I know it's Al b/c 13 protons is Al..but is it
c Al^3+ or
D Al
wait, they have to have an even # of protons and electrons, so it's C..b/c it's missing 3, and when you add 3 you really take 3 away

This post has been edited by 7_Deadly_Sins on Mon - Jan 25 2010 - 20:09:10

Task what's your aim?

less electrons = less negatives = more positive = 3+

randomtask2008

gonna poop this pic because i put effort into it and its worth more than an aim convo