Chemistry - September 2007

We are trying to help my child with his chemistry homework, but we can not find the answer for this question "What is the mass of sulfur-32 expressed in grams?"
Can anybody please help? Thanks!!!

2007-09-11 11:01:02 · 1 answers · asked by Anonymous

2007-09-11 10:41:31 · 2 answers · asked by Enrique L 1

2007-09-11 10:31:40 · 2 answers · asked by Jennifer V 1

The diameter of a certain atomic nucleus is 2.60 x 10-3 pm and its mass is 3.40 x 10-23 g. What is the density of the nucleus in grams per centimeter cubed? Assume the nucleus is a sphere with a volume equal to 4/3 π r3

To enter a number in exponential notation use an e for the exponent, e.g., 2.34 x 106 enter as 2.34e6 2.34 x 10-16 enter as 2.34e-16

2007-09-11 10:28:09 · 4 answers · asked by Anonymous

the whole question : Chlorine-35 is one isotope of chlorine. (35 is the mass number) chlorine-37 is another isotope of chlorine. How many protons and neutrons are in each isotope of chlorine?

i have it answered but idk if its right

2007-09-11 10:26:44 · 1 answers · asked by nothinbutnet2009 4

Calculate the volume occupied by 54.1 grams of a substance with a density of 3.26 grams/mL.

2007-09-11 10:22:40 · 4 answers · asked by Steven V 2

2007-09-11 10:14:29 · 4 answers · asked by david l 1

2007-09-11 09:41:22 · 2 answers · asked by Anonymous

is focalin a amphetamine or will it show up in a ua or a hair follical test

2007-09-11 09:36:14 · 1 answers · asked by linda r 1

Which of the following is a non-metal?

A. lithium, Li, Z = 3
B. bromine, Br, Z = 35
C. mercury, Hg, Z = 80
D. bismuth, Bi, Z = 83
E. sodium, Na, Z = 11

2007-09-11 09:07:08 · 14 answers · asked by Anonymous

What on earth is a cg??? and how does is it relate to g???
Help please, giving the 10 points for best explanation :/

2007-09-11 09:04:51 · 2 answers · asked by No. 01 2

Which of the following elements are the least reactive?

A. alkali metals
B. noble gases
C. halogens
D. alkaline earth metals
E. metalloids

2007-09-11 09:01:48 · 6 answers · asked by Anonymous

Bromine is the only nonmetal that is a liquid at room temperature. Consider the isotope
bromine-81, (80 above 35) Br. Select the combination which lists the correct atomic number, neutron number, and
mass number, respectively.

A. 35, 46, 81
B. 35, 81, 46
C. 81, 46, 35
D. 46, 81, 35
E. 35, 81, 116

2007-09-11 08:56:37 · 3 answers · asked by Anonymous

suggest the likely ions that would be formed by a calcium atom and how?

2007-09-11 08:50:23 · 2 answers · asked by monika 2

2007-09-11 08:28:09 · 2 answers · asked by ccutestuff2001 2

that use hydrogen, chlorine or sodium hydroxide.

for example, the haber process

2007-09-11 08:00:16 · 2 answers · asked by Anonymous

If so, do gas bubbles initially appear and then an additional process is required to remove them ?

2007-09-11 07:32:02 · 1 answers · asked by Anonymous

your boss needs 2 L of 2 M of HCl. You can only find 6 M of HCl. Show how you will make the 2 L of 2 M of HCl to keep your boss happy.

2007-09-11 07:09:38 · 3 answers · asked by Anonymous

2007-09-11 06:51:01 · 4 answers · asked by Anonymous

i have 2 products HCOOH and C2H5OH
i need them to react with H2SO4/ NaOH/ Na2Cr2O7/ PCl5/ NaBH4
to make as many organic products
please help!!

2007-09-11 06:17:42 · 2 answers · asked by mckenzie2 1

i dont want a long winded answer just a rough idea. Thanks.

2007-09-11 06:00:17 · 5 answers · asked by HoneyBadger 3

An excited ion emits radiation at a wavelength of 654.1 nm in the visible range of the spectrum. Calculate the frequency of a photon of this radiation (in hertz).

2007-09-11 05:30:22 · 1 answers · asked by sean b 1

Consider a solution separated from pure water by a semipermeable membrane that permits the passage of water,
but not solutes. Which statement is false?

a) Osmotic pressure depends upon the size of the solute molecules.

b)Osmosis is the movement of solvent from a region of high solvent concentration to a solution of lower solvent concentration.

c)Osmotic pressure is the pressure that must be applied to the solution to prevent the inflow of water.

d)Osmotic pressure could be eliminated if enough solute were added to the region of pure water.

explanation please thanx

2007-09-11 05:11:54 · 4 answers · asked by Anonymous

i have a hard time to understand stable molecule or not
Carbon :some time carbon have 0 formal charge, +1 formal charge, - 1 formal charge ( not stable)

can you explain it to me, and how do you know when they are stable or not by looking at molecule.
thank for all participates.

2007-09-11 05:10:36 · 2 answers · asked by phong pham 2

The combined total mass in grams of a beaker and pure water is 95.175g

1. Find the Volume of water in liters(hint: water has a density of 1g/mL)

2. What is the density (g/mL) of a solid with a mass of 4.75g and a volume of 6.2mL?

3. Find the mass (g) of a sample if 257mL of it has a specific gravity of 1.75?

4. Design an experiment to determine the density of lead and that of aluminum. Predict which one of the two metals has a higher density and explain your answers. (Hint: read this experiment carefully before you answer)

2007-09-11 05:03:59 · 5 answers · asked by Gumby 1

I'm doing an experiment in chemistry that involvesmath and measurements, and we're supposed to find Delta T using all these measurements and I'm not good at it at all. so if someone coujld please help me, that would be awesome!

here are the experiment details:

we have the mass of metal: 28.4g
mass of a calorimeter: 10.5g
mass of calorimeter with water in it: 466.5g
mass of calorimeter with water minus the mass of calorimeter: 456g

the temp. of water after 3 min: 25 degrees celcius.
what we had to do is drop a peace of lead that was in boiling water into room tem. water and watch how the temperature changed, but the temp did not change.
anyways....
the final temperature is: 25 degrees celsius
after this we have to determine how much heat the metal transferred to the water but there was no heat transferred so we just used 26 degrees celsius instead. so after that we need to use this eqaution: q= m times c times delta t, but i'm stuck from there. its long, but i'm stuck!

2007-09-11 04:57:03 · 8 answers · asked by singingfrog_92 2

I put a drop of NaOH into a beaker that had a buffer with a pH of 7 in it, and the pH rose by 0.01 and then i put 3 moe drops of NaOH and the pH rose by 0.01. How does the buffer control the pH.

Then I put a drop of HCl into another beaker with a buffer with a pH of 7 in it, and the pH rose by 0.05 and then i put 3 more drops of HCl into the same beaker and the pH lowered by 0.03. Then I put 6 more drops of HCl into the same beaker and the pH lowered by 0.01. why did the pH rise then lower, and how does the buffer control it.

2007-09-11 04:50:48 · 2 answers · asked by robert johnson 2

recipe
subscript
formula

2007-09-11 04:44:18 · 3 answers · asked by tia 3

i have several problems connected to molarity and don't know how to solve them.it's not necessery to solve all of the problems just if u could explain the general idea how to solve such problems and please write it in details.



1. The density of solution prepared by dissolving 5.46g of copper nitrate in 22.0 ml of water is 1.19g/ml. Calculate the mass of solute in 15ml of solution?


2. Calculate the molarity of a solution prepared by dissolving 9.43g of Na2CO3 on 150ml of water and then diluting to a final volume of 250ml.

3. How many ml of 1.54M H3PO4 hold 0.249 moles?

4. Calculate the moles of sodium hydroxide in 750ml 1.23M NaOH.

thanks very much for the help

2007-09-11 04:34:18 · 2 answers · asked by ju-isis 2

a)it is polar
b)it can ionize
c)it can hydrogen bond
d)it is very small

explanation please thanx

2007-09-11 04:30:33 · 2 answers · asked by Anonymous