Chemistry - January 2007

How do u type a *delta* the letter on microsoft word

2007-01-08 14:15:05 · 8 answers · asked by Anonymous

I'm doing observations for an experiment and would like to know what you would see if you made sodium chloride a saturated solution and then heated it up and made it saturated again. Would it just be crystals?

2007-01-08 14:11:08 · 2 answers · asked by untilyoucamealong04 3

[A] closer to C because carbon has a larger radius and this exerts greater control over the shared electron pair.
[B] closer to F because flourine has a higher electronegativity than carbon.
[C] closer to C because carbon has a lower electronegativity than flourine.
[D] an inadequate model since the bond is ionic
[E] centrally located directly between the C and F.

2007-01-08 14:06:53 · 3 answers · asked by Stephanie 2

explain how a balanced equation verifies the law od conservation of matter.

2007-01-08 14:02:18 · 5 answers · asked by Anonymous

if a chemical equation is impossible to balance, what is most likely the problem?

2007-01-08 14:00:29 · 3 answers · asked by Anonymous

this is a question from chemistry

2007-01-08 13:58:39 · 5 answers · asked by *MeG* 1

me and my brother are aruging over the right answer

and please no smartass answers like "well i know everything because im a geniuse" yet your 11 and live with your grandma in a ghetto with the worst school lernings

2007-01-08 13:57:47 · 2 answers · asked by Anonymous

[A] HCN, NO2, Ca(NO3)2
[B] PCl5, LiBr, Zn(OH)2
[C] KOH, CCl4, SF4
[D] NaH, CaF2, NaNH2
[E] CH20, H2S, NH3

2007-01-08 13:56:47 · 2 answers · asked by Stephanie 2

plzzzzzzzz help me with this question,,,,,i hv no clue.=[[[
thank u !

2007-01-08 13:56:40 · 1 answers · asked by Anonymous

The concentration of a solution
how completly the ions seperate

2007-01-08 13:56:38 · 2 answers · asked by rrhockeygoalie11 1

what are coefficients and why are they used?

2007-01-08 13:55:47 · 4 answers · asked by Anonymous

how are chemical reactions described? give an example.

2007-01-08 13:54:26 · 4 answers · asked by Anonymous

when oil and water are mixed, thay never react whit each other. but when hydrogen gas and oxygen gas are mixed together, they can react to produce water. why do some substances react with each other, while othere do not?

2007-01-08 13:51:40 · 1 answers · asked by Anonymous

what occurs during a chemical reaction? what are the names given to the various substances that are invilved in a chemical reaction?

2007-01-08 13:45:20 · 2 answers · asked by Anonymous

Does anyone know how much a digital scale would cost that can messure acurate down to 1mg?

2007-01-08 13:44:12 · 3 answers · asked by Im not stupid i just dont care 2

when Mg reacts with FeCI3, magnesium will replace chlorine in the compound.

2007-01-08 13:41:37 · 2 answers · asked by Anonymous

in a single-replacement reaction, there is only one product.

2007-01-08 13:40:07 · 2 answers · asked by Anonymous

in direct combination reactions, complex substances form simpler sucstances.

2007-01-08 13:38:26 · 12 answers · asked by Anonymous

Why does potassium nitrate dissolve much more with increasing temperatures?

2007-01-08 13:36:07 · 5 answers · asked by untilyoucamealong04 3

coefficients are written in front of chemical formulas to balance equations.

2007-01-08 13:35:10 · 17 answers · asked by Anonymous

I need to crush up my medication and weigh it out in grams. Actually it will be divided into a half gram dose or one-quarter gram dose.I need to know how a half gram and quarter gram is written so I can choose the right scale to buy. Thanks......

2007-01-08 13:29:04 · 7 answers · asked by peter h 1

2007-01-08 13:25:46 · 5 answers · asked by kimberly k 1

1.78 grams of an unknown solute is dissolved in 22.43 grams of a solvent having a K(sub f) of 7.11 C/m. The normal freezing point of the solvent is 48.91 C. The solution freezes at 46.38 C. Find the molecular mass of the unknown.

All I need is an equation to solve for this problem, thanks!

2007-01-08 13:24:15 · 1 answers · asked by shanerox2005 1

Here is the problem
Calculate delta E (change in internal energy) and determine whether the process is endothermic or exothermic for the following cases:
a a system absorbs 85 kj of heat from it's surroundings while doing 29 kj of work on the surroundings.
B. Q equals 1.50 kj and w equals -.657kj
c the system releases 57.5 kj of heat while doing 13.5 kj of work on the surroundings.
answers.
a 56kj endothermic
b. .84kj endo
c. -71 exothermic

What I don't understand is why the formula changes. I thought it is always supposed to be change in E = q + w but for a it is q-w, b it is q+w, and c it is -(q+w). Could someone please explain? It's probably something simple I just am missing. Thanks a lot.

2007-01-08 13:23:59 · 2 answers · asked by Sam 3

what is the solubility of :
suger
napthalene
sulfer
salt
and PDB (para-diclorabenzyne)

any of the answears would be great

2007-01-08 13:13:14 · 4 answers · asked by Anonymous

a. CsF
b. CsCl
c. NaCl
d. NaF
e. LiF

2007-01-08 13:12:47 · 3 answers · asked by Stephanie 2

The enthalpy of fusion of ethanol is 5.02 kJ/mol, and its enthalpy of vaporization is 38.56 kJ/mol. The specific heats of solid and liquid ethanol are 0.97 J/gK and 2.3 J/gK, respectively. How much heat is required to convert 62.0 g of ethanol at -135°C to the vapor phase at 78°C? Please, if anyone can figure this out, thank you so very much.

2007-01-08 13:07:28 · 3 answers · asked by magicalplaygirl 1

2007-01-08 13:00:25 · 2 answers · asked by sharon 1

the substances formed as a result of a chemical reactionare called reactants.

2007-01-08 13:00:09 · 15 answers · asked by Anonymous

Which of the salts (sodium chloride, potassium nitrate and calcium hydroxide) could dissolve much more with increasing temperatures, and why?

2007-01-08 12:52:09 · 1 answers · asked by untilyoucamealong04 3