Chemistry - August 2007

Nitrogen is made up of two isotopes, N-14 and N-15. Given nitrogen's atomic weight of 13.007, what is the percent abundance of each isotope?

2007-08-22 17:37:46 · 4 answers · asked by d 1

how to prepare methanol (CH3OH) in the lab?
Thanks.

2007-08-22 17:13:50 · 1 answers · asked by Sicheng 1

2007-08-22 17:09:06 · 8 answers · asked by Anonymous

A gaseous compound consists of element X (at. wt. = 12) and element Y (at. wt. = 1). Its empirical formula is XY2 and its density is 1.25 g/L at STP. What is its molecular formula?

2007-08-22 17:08:14 · 4 answers · asked by BioSci 1

We had a quiz in chemistry and I was just wondering if my answers are right. The exercise was about "CORE ELECTRONIC CONFIGURATION", and these are my answers.:

Given/Solution:

1. [Na] Sodium = [Na] 2p6 3s1<--- Electronic Configuration

Last M: 3 and the Valence: 1

2. [I] Iodine = [I] 4d10 5d5

Last M: 5 and the Valence: 5

3. [Ar] Argon = [Ar] 3d4 4s2

Last M: 4 and the Valence: 2

-----> If my answers are wrong please explain. Thank you!

2007-08-22 16:55:16 · 1 answers · asked by Light 3

Cumene is a cmpd containing only C and H that is used in the production of aceton and phenol in the chemical industry. Combusetioni of 47.6 mg of cumene produces some Co2 and 42.8 mg of water. The molar mass is between 115-125. determin the mpirical formula nad molecualr formula.Please show work.

i have no idea what im doin wrong here. Seriously

2007-08-22 16:07:06 · 1 answers · asked by Krazym0nkey 2

How many grams of oxygen are necessary to produce 4.5 moles of NO2?

How many molecules of water are produced when 2.25 moles of ammonia are completely reacted?

2007-08-22 15:47:56 · 2 answers · asked by Bucky 1

Arrange the following in expected order of solubility in water from lowest to highest: I2, KI, and C8H8? Could someone explain it to me plz???

2007-08-22 15:44:44 · 4 answers · asked by Dom Dom Damdum 3

So far I have Sodium 23(2)
Sulfur 32(1)
Oxygen 16(4)
but not sure if that helps need to find

Na____S____O____

2007-08-22 15:44:16 · 1 answers · asked by Bucky 1

Could someone check to see if I did this right? I was given an atomic number or symbol of these atoms and I had to find the rest. Should I round up the neutron number or one of the others?

1)Atomic number: 11 Symbol: Na Mass Number: 22.989 Proton Number:11 Neutron Number:11 Electron Number:11

2)Atomic number: 13 Symbol: Al Mass Number: 26.981 Proton Number:13 Neutron Number:13 Electron Number:13

3)Atomic number: 26 Symbol: Fe Mass Number: 55.847 Proton Number:26 Neutron Number:29 Electron Number:26

2007-08-22 15:41:59 · 5 answers · asked by Bucky 1

2007-08-22 15:17:04 · 8 answers · asked by Darryl H 1

Salt
Sugar
Mentos
Flat Coke
Halls
Water
Carrots
Gum
Paper
Rubbing Alcohal
Milk
Aloe Lip Chap
Batteries ( used )

Please give me something that makes a little/big explosion out of this its inside my house so not to big. Its for a Science Project and I need to know how it explodes worth 22 grades ( I am in Advanced Chemistry For 8th Grade )

Whoever gives me an accurate response gets voted as Best Answer! And wins 12 Points!

2007-08-22 14:15:55 · 3 answers · asked by Anonymous

Please tell me do they equal. If so why would they and what could you use to measure them! PLEASE!!! "Most importantly what could you use to measure them and why?"

2007-08-22 14:14:25 · 9 answers · asked by Anonymous

Is it hydrogen, van der waals or ionic? I'm pretty sure it's not hydrogen, since water is an example of where hydrogen bonds are pretty strong. But I'm not sure which one it is, since they're all weak bonds.

2007-08-22 14:04:21 · 4 answers · asked by vendetta4hire 3

hey guys! could you please help me about the aromacity of
compounds? and whats the difference between anthracene
and phenanthrene, the 2 simplest compound? please give me
facts about them..

2007-08-22 13:46:15 · 4 answers · asked by Alden ^^ 2

I just want an explanation

2007-08-22 13:12:20 · 6 answers · asked by Dopeboy 1

Also, what chemistry occurs in the human body on a day to day basis, and what chemistry occurs in the car and computer on a day to day basis.

Thanks!

2007-08-22 12:49:48 · 1 answers · asked by Fido 1

I like all the compounds of Copper (Except the really poisonus ones lol) but I was wandering if anyone knew how to produce some of these compounds. If it is reacting the acid with the metal can someone tell me how to get rid of the remaing acid while producing the compound. (Please no safety warnings)

2007-08-22 11:57:44 · 2 answers · asked by Snowman6317 2

Does anyone know any helpful tricks in knowing how many valence electrons a given element has?

2007-08-22 11:35:41 · 5 answers · asked by behindthemask 2

Give me a simple way to do that is proven to work, not difficult enough to a degree where i cant understand it. ( I am in AP chem)

2007-08-22 11:25:08 · 2 answers · asked by shashank 2

2007-08-22 11:19:34 · 4 answers · asked by jhazle 1

2007-08-22 11:04:26 · 5 answers · asked by dad_hy 1

does it go boom? blamo? create monkeys? what?

2007-08-22 11:02:16 · 14 answers · asked by benny b 1

2007-08-22 10:46:10 · 2 answers · asked by dad_hy 1

The density of benzene at 15 C is .8787 g/mL. Calculate the mass of .1500L of benzene at this temperature? What are the steps to do this?

Also.... The density of titanium metal is 4.51g/cm3 at 25 C. what mass of titanium displaces 68.8mL of water at 25 C?

2007-08-22 10:33:32 · 3 answers · asked by john s 3

Name these ions or give the ion's formula:
1) _______ o2^2-
2) _______ HCOO^1-
3)_______ferrous
4)_______ plumbic
5)_______ oxalate
6)_______Hg^2+ (old)
7)_______S2O3^2-
8)_______CH3COO^1-
9)_______hyponitrite
10)______OH^1-
11)______ammonium
12)______ClO2^1-
13)______tin(IV)
14_______perbromate

2007-08-22 09:22:07 · 1 answers · asked by Karen R 1

14. which gas will diffuse mostly rapidly at the same temperature and pressure?
a)fluorine, F2
b) Chlorine Cl2
c) ammonia, NH3
d)nitrogen(II) oxide NO

15. Which household product contains acetic acid, CH3COOH?
a) bleach
b) vinegar
c) drain cleaner
d) household ammonia

16. When the expression is balanced using smallest whole numbers, what is the coefficient of CO?
_K2CO3 + _C > _CO + _K
a)2
b)3
c)4
d)6

17. A 500.oo cm3 container is filled with 2.20 g of carbon dioxide gas, CO2 at 127 C. What is the pressure exerted by the gas?
a) 3.32 x 10^-1 kPa
b) 1.06 x 10^2 kPa
c) 3.32 x 10^2 kPa
d) 1.46 x 10^4 kPa

19. What is the empirical formula of a compound that contains 6.42 g sulfur, S, and 22.8 g flourine, F?
a)SF2
b)SF3
c) SF4
d)SF6

20. what is the total number of electrons in a sodium ion, Na+?
a) 1
b) 10
c) 11
d) 12

21. what mass of water is released, when 10.0 g of MgSO47H2O is completely dehydrated?
MgSO47H20 > MgSO4 + 7H2O
a)0.0407 g
b)0.285 g
c) 5.12 g
d) 51.1 g

2007-08-22 09:01:35 · 4 answers · asked by ashley t 1

like the precedure to reveal fingerprints

2007-08-22 08:22:04 · 2 answers · asked by sadimani 1

a 1s^2 2s^2 2p^6

b 1s^2 2s^2 2p^2

c 1s^2 2s^2 2p^6 3s^2

D 1s^2 2s^2 2p^6 3s^2 3p^2

2007-08-22 07:52:55 · 3 answers · asked by Anonymous

A 15.67 g sample of a hydrate of magnesium carbonate was carefully heated, without decomposing the carbonate, to drive off the water. The mass was reduced to 7.58g.
Also, can you explain how you do it?

2007-08-22 07:49:21 · 3 answers · asked by Vinny L 3