Can You Guys Help Me With A Few Chemistry Questions

A few chemistry questions...Help would be great!?

Hey guys, just have a few basic biochem Q's, help to any of them would be greatly appreciated!

1 a) How many grams of NaOH would 1 Litre of a 1 M of a solution contain?

b) how many mmoles are there in 1 mL of this solution?

2. You are required to make a solution of NaHCO3 with a concentration of umoles/ml.
a) what molarity is this?
b) how many grams of NaHCO3 are needed to make up 250Mls of this solution?
4. How would you prepare the following solutions?
a)1 L of 0.5 M (NH4)2SO4 from solid (NH4)2SO4
b)37ml of 0.8 M H2SO4 from 17.8 M H2SO4
c)3ml of 0.2 M NaOH from 6M NaOH
d) 10 ml MgCl2 with a concentration of 1 umole/ml
e) 100ml of a 15 mM solution of NaCl from a stock solution of 1.5M
5. You require a glucose solution of 10 uMoles/ml. All you have is a solution of 0.2 M glucose. What is the dilution factor?

Any help would be awesome guys!

Can you guys help me with a few chemistry questions?

Question 1

Which of the following solids would be the most malleable?
Answers:

CuO

SiC

C25H52

Zn


Question 2

Which of the following solids would have the highest melting point?
Answers:

NH3

H2O

C6H6

LiCl


Question 4

Which of these are allotropes?
Answers:

oxygen gas (O2) and ozone (O3)

glass (SiO2) and quartz (SiO2)

water (H2O) and hydrogen peroxide (H2O2)

diamond (C) and buckminsterfullerene (C60)



Question 8

Which of these is a property of amorphous solids?
Answers:

highly ordered network of particles

strong ionic bonds

large network of covalent bonds

disordered structure

Chemistry questions...can you help me?

So I just have a few questions I need answered that I'm not sure of. There were about 30 in all, and I have them all done except these last 4.

2. Use LeChatelier's principle to explain how an equilibrium can be shifted so that atmospheric nitrogen can be combined with hydrogen to produce ammonia according to this equation.
N2 (g) + 3H2 (g) <==> 2NH3 (g) + heat

11. Explain why the reaction between sodium carbonate and copper(II) sulfate goes to completion.

13. Write a balanced equation for the reaction when sodium carbonate solution and hydrochloric acid solution are mixed.

14. Explain why the reaction between sodium carbonate and hydrochloric acid goes to completion.

That's all...if anyone could help please, even if it's just one. Thanks guys :)

A few chemistry questions?

1. A piece of wood is 1 meter long, 25 centimeters wide, and 13 millimeters wide.
a) Calculate the density of the wood in g/cm3, if the mass of the wood is 1750g.
b) Identify the kind of wood by looking up densities of common species of wood.
(if you give me a good explination for A, i'm sure i can do B by myself)

2. Calculate the densities of diet and regular soda given the following data:
a) Volume of the liquid = 12oz and 29.57ml - 1oz
b) Mass of empty soda can = 12g
c) Mass of full can of diet soda = 370g
d) Mass of full can of regular soda = 390g

PLEASE give me thorough answers.
I'm really not trying to cheat or take a short cut. I really don't understand these questions. I go to a school where teachers have way to many students to help 1 on 1, and it's impossible to make an appointment with my teacher when the assignment is due the next day. My parents can't even help me with this. So, you guys are my last hope. Please help!

10 points goes to a good explination.

Chemistry help please!?

Can you guys help me with a few questions from my homework.

1. What STARTING element undergoes alpha decay to yield uranium-234 (U) as a PRODUCT? Again, express your answer as symbol-mass, for instance U-234.

2.Cobalt-53 (Co) is unusual because it decays by emitting a proton. What is the resulting element that remains after cobalt has undergone this unusual form of decay? Again, express your answer in the Co-53 format.

3.What are the coefficients used to balance the following equation, AlCl3 + Ca --> CaCl2 + Al.

4.What element is the product of dysprosium-166 (Dy) undergoing beta and gamma decay.

Can someone help me with these two chemistry questions on molality?

1. You need to know the molality formula
m = moles of substance/ kg of solvent
Then you need to do a few conversions to get your iodine and CCl4 into the proper units.
to convert 125 g you would need to divide by 1000
125 g I x (1 kg /1000 g) = .125 kg I
Next, divide your given g of CCl4 by the molar mass of CCl4 to get the moles of CCl4. (note: the period is just to indicate that the 0 is significant)
750. g CCl4 x (1 mol CCl4/153.823 g CCl4) = 4.88 mol CCl4
Then, just plug your moles CCl4 and kg of I into your original formula, the one for molality

m = (4.88 mol CCl4/ .125 kg) = 39.0 mol/kg

Follow the same steps just with the new values for the other problem. Note the # you want to divide the lead by is really just the atomic mass of lead (Pb on the periodic table of elements) Your answer might slightly differ from mine if you use a different periodic table, but they should be close.

Hi guys, I have a few chemistry questions, Please show work :)?

1) A 0.58 M solution contains 0.58 mols / L. Thus, 0.95L will contain 0.95 x 0.58 mols, = 0.551 mols (or, 551 milli mols). 2) Without knowing the volume taken up by 67 grams of LiF, it is not possible to calculate exactly how much water should be added. The true answer to this question is as follows: the molecular weight of LiF is 25.94. That is, 1 mol of LiF weighs 25.94 grams. 67 grams thus is 2.58 mols (67 / 25.94) or about 2.6 mols. A 2.6 M solution is 2.6 mols / L. You should dissolve the 67 grams in, say, 600 mL of water and then adde xtra water to a FINAL VOLUME of 1L. The actual volume of water the 67 grams is disolved in is 1L minus the volume taken up by the 67 grams LiF. 3) Avagadros number is 6 x 10^23. That is, a mol of a substance contains 6 x 10^23 atoms / molecules. Thus 3.5 x 10^22 molecules of sugar is 0.058 mols of sugar (3.5 / 6 / 10). Thus, 3.5 x 10^22 molecules in a FINAL VOLUME of 25 mL is 0.058 x 40 = 2.32 M. 4) 0.85 M means 0.85 mols / L. Thus, the number of mols in 2.1 L is 2.1 x 0.85 = 1.785 mols.

Clarifcation: Avagadros number (6 x 10^23) is the number os atoms or molecules in 1 mol of any substance. For example, NaCl has a molecular weight of 58.55 (I think!). So one mol of NaCl is 58.55 grams and that contains 6 x 10^23 molecules. The molecular weight of water is 18. So 18 grams (1 mol) of water contains 6 X 10^23 molecules. At the end of the day, molarity tells us the number of molecules per total volume. But, molarity can also be expressed as number of grams per total volume (the gram mol).

3.5 divided by 6 divided by 10 (or (3.5 x 10^22) divided by (6 x 10^23).

25 mL goes into 1000 mL 40 times. The amount of mols given is dissolved in a final volume of 25 mL, not 1 L, so you must multiply by 40 for the amount in 1L..

Can you guys help with some chem hw?

Ah, a little stoichiometry homework! Fun!

Okay, there's a few things you have to remember first: 1 mole of ANYTHING contains 6.022e23 (meaning 6.022x10^23) units. Also, remember that the mass of one mole is numerically equal to the formula weight, except molar mass has the unit of grams per mole.

We need to figure out first how many moles are represented by 21.3 grams of Al(NO3)3. That means we need to know its molar mass. Go ahead and grab your periodic table and a calculator.

1 mol Al = 1 x 27.0 = 27.0
3 mol N = 3 x 14.0 = 42.0
9 mol O = 9 x 16.0 = 144

Adding those will give you the molar mass of aluminum nitrate: 213 g/mol.

Now, let's convert:

21.3 g Al(NO3)3 x (1 mol Al(NO3)3 / 213 g Al(NO3)3) = 0.100 mol Al(NO3)3

Now we need to figure out how many moles of oxygen are represented in 0.100 mol Al(NO3)3. Because the formula contains 9 oxygen atoms, we know that 1 mole of aluminum nitrate contains 9 moles of oxygen atoms.

0.100 mol Al(NO3)3 x (9 mol O / 1 mol Al(NO3)3) = 0.900 mol O

Now all that's left is to figure out how many oxygen atoms are represented by 0.900 mol.

0.900 mol O x (6.022e23 O atoms / 1 mol O) = 5.42e23 O atoms.

And that's about it.

For the second part, you only need to convert 1 atom of U-235 to moles, then to grams. Use the same techniques I showed you in the first problem, and you'll be able to get it. Good luck!