Chemistry - February 2007

ok.... so we are doing conversions with moles and grams in chemistry right, well i know how to do them once the problem is set up, the problem is how do i know what formulas to use with what... because they are so many conversion factors to go with turning moles into grams and molecules to moles and whatnot. its hard to keep track of how to set up your probelm depending on that type of coversion. ... yeah, so how do i remember this?

2007-02-22 11:46:38 · 3 answers · asked by Stephanie 3

2007-02-22 11:38:36 · 6 answers · asked by francois7430 2

HClO4 HOAc HCN HF
1x10^7 1.76x10^-5 4.93x10^-10 3.53x10^-4
which shows the conjugate bases listed by increasing strength?
A. ClO4-, F-, OAc-, CN-
B. CN-, F-, OAc-, ClO4-
C. CN-, OAc-, F-, CO4-
D. CN-, CLO4-, F-, OAc-
ClO4-, OAc-, CN-, F-

2007-02-22 11:36:00 · 3 answers · asked by galdon885 1

2007-02-22 10:59:17 · 2 answers · asked by Snowandskibaby 2

all the atomic masses have a lot of numbers after the decimal

2007-02-22 10:56:58 · 6 answers · asked by thiskidthattheylove 2

what is the total number of lone pair (nonbonding pairs) in NCl3?

2007-02-22 10:52:20 · 1 answers · asked by Alan l 1

Hello, I'm trying to figure this one out:
"Calculate the volume (mL) of 0.100 M H3PO4 required to neutralize 30.0 mL of 0.050 M Ca(OH)2."

Am I supposed to use a certain formula for this? How do I do this problem? Where should I start this? I read the text book but it doesn't clearly explain How I do this.

2007-02-22 10:48:08 · 1 answers · asked by Anonymous

An idea of what is happening on a chemical or molecular level would be the best

2007-02-22 10:38:17 · 1 answers · asked by Samuel H 1

This is about the 50th time I am asking for help, so bear with me. I need to find out the answers to the following questions, so if you could answer any one or all of them, that would be greatly appreciated! Please put the number of the one you solved next to it. Here is the info I have(this was a lab)

mass of empty crucible- 6.31 grams
mass of crucible with MgSO4 (that big black dot goes here) n H2O- 11.33 grams
mass of crucible and anhydrous MgSO4- 8.71
Here are the questions:

1. Calculate the mass and number of moles of anhydrous MgSO4.
2. calculate the percent of water in the hydrated compound.
3. calculate the ration of moles of water to moles of anhydrous MgSO4.
4. Write the value of n and the formula for MgSO4 (big dot) H2O
5. The accepted value for n is 7. Calculate the percent error for the value of n.

That's all! If you could show how you got the an, that's be great. I know that it's a lot, but these questions are making me really comfused. Thanks!! ;)

2007-02-22 10:34:18 · 1 answers · asked by Dana Mulder 4

ex. quest. ----what is the density of oxygen at STP?
where do you begin??

2007-02-22 10:33:33 · 2 answers · asked by postpunkchic_x3 1

how does artificial fires start?
how does natural fire start?
what stops a fire?
what does water have that stops a fire?

ect. thanks

2007-02-22 10:32:59 · 8 answers · asked by heyheyhey 3

2007-02-22 10:26:25 · 2 answers · asked by Anonymous

N2O4(g) ↔ 2NO2(g)

is an equilibrium reaction at some temperature with an equilibrium constant K = 4.00 x 10−7.
If the intial condition is pure N2O4(g) at a concentration of 1.88 mol/L what is the equilibrium concentration of NO2 in mol/L ?


HINT : Since K is small you can use the approximation for Small Equilibrium constants, as in your text

HINT : in the equilibrium expression the product is written as 2x
Since the numerator in the expression for the equilibrium constant
is the product concentration raised to the stochiometric coefficient,
it becomes (2x)2

2007-02-22 10:24:26 · 1 answers · asked by becky 1

a) CH2=CHF


b) CHCl=CH-CH2Cl


c) ClBrCHCl


d) CHCl=CH-CH2Br


e) 1,1-dichloroethene

2007-02-22 10:20:04 · 3 answers · asked by garture 1

I have to do a prelab for my physical science class and I'm so lost! We also have to design an experiment to separate water into its component parts, and explain how hydrolysis works using the kinetic theory. thanks to anyone who answers.

2007-02-22 10:10:16 · 1 answers · asked by Anonymous

I want to use the product below (Dry Out Dehumidifier) to dehumidify a workspace, but I don't want to dump a bunch of gross stuff into the earth. I got varying information when I researched this. Any chemists who know? Thanks!

http://www.jetchemical.com/productinfo.html?prod_id=1

2007-02-22 09:55:04 · 4 answers · asked by ccb 1

Which of the following compounds can exist as cis and trans isomers ?


a) CHCl=CHCl


b) CH2=CH-CHCl2


c) HClCFCl


d) CBrH=CH-CH2Cl


e) 1,1-dichloroethene

2007-02-22 09:50:49 · 2 answers · asked by garture 1

How many different structual formulas can be written for C6H14

Include straight chain and branched chain compounds.

2007-02-22 09:49:17 · 1 answers · asked by garture 1

How many different structual formulas can be written for C6H14

Include straight chain and branched chain compounds.

2007-02-22 09:49:11 · 2 answers · asked by garture 1

Some types of bacteria are killed by being heated to 150°C for 30 minutes. Explain why they could be killed in a pressure cooker, but not in boiling water in an open pan.

2007-02-22 09:36:54 · 1 answers · asked by shopaholic 3

if 0.2178 g of a diprotic solid acid is neutralized by 44.81 mL of 0.0953 M NaOH, how do u calculate the mola mass of the solid acid???

is there a formula to this? :/

2007-02-22 09:33:18 · 1 answers · asked by stardust6547 2

0.00032 M

I keep doing it but i think i am messing up with the qudratic equation

2007-02-22 09:27:33 · 1 answers · asked by mitch v 1

REACTIONS
1. What is the reaction for the burning of Mg ion air?
2. What is the reaction for the Mg product and water?

BALANCING EQUATIONS
1. What is the balanced reaction for zinc and hydrochloric acid?
Zn + HCl --> ___?
2. What is the balanced reaction when zinc reacts with lead(II) nitrate? Zn + Pb(NO3)2 -->____?

2007-02-22 09:12:42 · 1 answers · asked by SICK MY DUCK! 1

2007-02-22 09:07:38 · 1 answers · asked by Anonymous

Sorry the pH is 10.00

2007-02-22 09:03:02 · 2 answers · asked by mitch v 1

the titrationcurve was determined that at midpoint in the buffer region the ph was 4.50. what are pKa and Ka, please shows me work. thanks in advance

2007-02-22 08:46:59 · 1 answers · asked by phong pham 2

2007-02-22 08:40:43 · 15 answers · asked by Einstein 7

2007-02-22 08:36:45 · 1 answers · asked by frank f 2

2007-02-22 08:35:54 · 2 answers · asked by frank f 2

i am going to a junior in high school next year. i am taking Honors Physics Lab. I also want to take either microbiology or organic chemistry since i want to major in pharmacy. which one is easierr, Microbiology or organic Chemistry? will it be easier to take Physics and microbiology or physics and organic chemistry?

2007-02-22 08:32:31 · 3 answers · asked by Anonymous