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anonymous
 3 years ago
How many molecules of H2O are there in 1.0 g of H2O?
anonymous
 3 years ago
How many molecules of H2O are there in 1.0 g of H2O?

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anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0in 1.0 grams of H2O. okay so.. You are given grams (mass). To go from mass to molecules, you have to convert: Mass > Moles > Molecules. To go from mass to moles, Divide by the molecular weight. To go from moles to molecules, multiply by 6.02 x 10^23.

abb0t
 3 years ago
Best ResponseYou've already chosen the best response.0convert to moles. then use avogradro's number \(6.022 \times 10^{23}\frac{ atoms }{ mol }\)

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0I do not know how to do this ..

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0Sure you do ;) Let's take it step by step. You are given 1 gram of H2O, and need to divide this by the molecular weight. The molecular weight can be found by adding up all the individual masses of the atoms. How many atoms of Hydrogen are in H2O? How many atoms of Oxygen are in H2O? Multiply the number of atoms of Hydrogen by the atomic mass of hydrogen. Multiply the number of atoms of Oxygen by the atomic mass of oxygen. Add these two values together, what do you get?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.02 atoms in Hydrogen and 1 atom of Oxygen. atomic mass of hydrogen is 1 2*1=1 atomic mass of oxygen is 15.9994 15.994*1=15.9994 Added together is 16.9994

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Do you have it now? Or do you still need help?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0I don't know if 16.9994 is the answer?

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Hang on. I'll figure it out

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3No. Obviously no. It's way too small.

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0I have no clue what I am doing

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Do you know what a mole is?

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3That might be your trouble. A mole of any compound or element is the molecular weight in grams. So if you had a scale and wanted to weigh out a mole of water, you would weigh out 18 g because 2H=2, O = 16 and the molecular weight is 18

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Do you know how to find molecular weight?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0I looked it up online

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3So I take that to be a yes?

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Do you have a periodic table?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0I looked up the weight online. and I do, yes

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Find the molecular weight of HCl

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3So a mole of HCl is 36.46094 grams.

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Now here is the next important point: a mole of "stuff" has 6.023 x 10^23 molecules in it.

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3That's Avagadro's number. That is something you cannot reason out you have to learn it.

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3So lets say I have some carbon. A mole of carbon is 12 grams. I have 24 grams. How many moles is that?

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Yes. Good. Now remember each mole is 6.023 x 10^23 molecules so how many molecules of carbon do I have?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0I suppose I do not understand how 6.023 X 10^23 works because if there are 2 moles how exactly do I work that in?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0If you have 1 mole of "stuff", you have exactly 6.023 x 10^23 molecules. If you have 2 moles of stuff, you would multiply Avogadro's number by 2.

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Would you agree that 2 moles is twice as much as 1 mole and so I should multiply by 2?

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3And \[2(6.023 \times 10^{23)}=12.046 \times 10^{23}\]

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3So that is the number of molecules in 2 moles of carbon.

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Ok. dimensionx will help you now. Too many cooks.

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0so we aren't really solving the entire equation because when I did that I had a ginormous number

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0@Mertsj sorry didn't mean to tread on you xD blahhhh, We are taking it stepbystep ;)

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0So we know that we have 2 Hydrogens and 1 Oxygen. 2 x Hydrogen 1 x Oxygen 2 x (1) = 2 1 x (16) = 16 Total Molecular Weight = 18

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0Do you understand how I got this value?

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3So why isn't this problem done yet?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0because I do know how to apply this... I am thinking at 18 is the answer. I am sorry It is just not clicking.

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.318 grams is 1 mole of water. How many moles is 9 grams of water?

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3That would be 9/18 right?

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3How many moles is 3 grams of water?

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Just tell me the fraction.

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3I think I see a pattern here: I will draw it because I want you to see it too.

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3How many moles is 1 g water?

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Now we know we have 1/18 mole of water and each mole has 6.023 x 10^23 molecules. So we should multiply 1/18 by 6.023 x 10^23 to find how many molecules we have.

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0I am not getting those numbers..

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Type 6.023 divided by 18 equals

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Did you get .334611111111 ??

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3That has to be multiplied by 10^23 but that is WAAAAAAY to many zeros so we we just write it: \[.33461111 \times 10^{23}\]

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3However we have two problems. 1. That is too many significant digits 2. It is not in scientific notation.

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3So we will round it to .33 So now we have: \[.33 \times 10^{23}\]

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3But that is still not scientific notation so we will change the .33 to 3.3 but that means we have to change the exponent to 22: \[3.3 \times 10^{22}\]

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Excellent. Now. You can do these problems without really understanding them if you know or can find the right conversion factors and just set it up so that the units turn out right. Do you care to see that?

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Start with what is given: 1 g water

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3\[1 gram water \times \frac{1 mole water}{18g water} \times \frac{6.023 x 10^{23}molecules}{1 mole water}\]

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Notice how the units cancel just like numbers and you end up with the number of molecules which is just what the problem asked for.

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3So if the units come out right, you know you have the numbers right.

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0so that would translate to 1 x 18/18= 1 x 6.023x10^23/18?

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3yes. multiply all the numerators and divide by all the denominators.

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3But the powers of 10...just leave that til the end.

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0when I did that I got a massive number..since I already knew it 3.3x10^22 it made sense how do I figure it out when there is no decimal?

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3The exponent 22 means move the decimal point 22 places to the right. That's why we use scientific notation. Who wants to mess with all those zeros?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0right, it is like I get it for a second then it all goes away. when I did it using the formula you gave canceling everything out I just got a massive number 334111111111...

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Exactly. You can enter it into your calculator if you use the EE button to enter the exponent. At least that's the way it is on my calculator. I enter 6.023 EE23 and then it manages the exponents and scientific thing for me.

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0Oh I get it! .... so when it is a .xy number you move the decimal and it becomes x.y^22 instead of ^23. and if it turns out a x.y number it stays ^23?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0OH MY GOD YOU ARE POSITIVELY AMAZING AND YOU HAVE NO IDEA HOW MUCH I APPRECIATE YOUR TIME AND PATIENCE! In the future if I come across a problem like this I would like to run it by you so you check it? Or any other problems that threaten a brain aneurysm lol

Mertsj
 3 years ago
Best ResponseYou've already chosen the best response.3Glad to be of service. Remember Jesus said, "Whoever would be great among you, let him be your servant."

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0Beautiful. I wouldn't want to call you a servant but, I love to learn from those who know more than I do.
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