Chemistry - May 2007

2007-05-20 11:02:28 · 2 answers · asked by kaitlin_1952 1

The heat of vaporization for steam is 2.26 kJ/g at 100. oC. How much energy is needed to vaporize 100. g of water at 100. oC to steam at 100. oC?

2007-05-20 10:51:31 · 4 answers · asked by jenn ayr 2

i know the answer but i need to see step by step and what to cancel out.

if 6.02x 10^23 molecules of N*2+3H*2->2NH*3, the total number of molecules of NH*3 produced.

2007-05-20 10:30:01 · 1 answers · asked by Anonymous

Let's say a cup of coffee. if I pour twelve fluid oz of coffee in a mug. would it stay hot longer in a short/wide mug or a tall/skinny mug (if it is different at all)? Thanks!

2007-05-20 10:20:55 · 7 answers · asked by Anonymous

2007-05-20 10:19:36 · 2 answers · asked by BBrittney 1

2007-05-20 10:17:09 · 2 answers · asked by crazy4CSI: 1

2007-05-20 10:16:40 · 7 answers · asked by Anonymous

2007-05-20 10:12:14 · 2 answers · asked by Anonymous

I cant seem to find a metalloid thats either non-toxic or dangerous in any way

2007-05-20 10:10:34 · 2 answers · asked by Laura R 1

An aluminum pan with a mass of 20.0 g is placed in an oven so that its temperature changes from 25 degrees C to 120 degrees C. How much heat was added to the pan?

2007-05-20 10:04:55 · 2 answers · asked by Anonymous

2007-05-20 10:02:22 · 6 answers · asked by Anonymous

What is the maximum mass of NH3 that can be produced when 49.0g of Mg3N2 and 25.0g H2O react. I just dont know how to set it up. What I did was 49.0g Mg3N2/1 * 1mol Mg3N2/100.9284g Mg3N2 * 2mol NH3/1mol Mg3N2= 0.97 mols which should be about 16.52 g. However when I put this it it came up wrong.

Thanks
Bibbity

2007-05-20 09:58:45 · 1 answers · asked by bibbitybobbyboo22 2

I got that it should be about 19.71 but that keeps showing us as wrong. Also in the question it says "Use a molar mass with at least as many sig figs as the data given. I'm not very good with sig figs (they dont make sense) so I'm sure why I'm getting that question wrong.

All feedback is apperciated.

2007-05-20 09:50:28 · 2 answers · asked by bibbitybobbyboo22 2

2007-05-20 09:45:00 · 1 answers · asked by Anonymous

2007-05-20 09:38:10 · 1 answers · asked by joe h 1

16H+ + 2MnO4-2 → 2Mn+2 + 8H2O + 10CO2

2007-05-20 09:28:22 · 2 answers · asked by kered628 3

1. 500mL of a solution contain 0.1 mole of acetic acid, HC2H3O2. The solution is diluted with water to the 1L mark. Calculate the molarity of the resulting solution.

2. What is the concentration of a solution formed by diluting 300mL of a solution containing 0.1 mole of HCL to 6L

2007-05-20 09:18:20 · 1 answers · asked by Anonymous

2007-05-20 08:31:45 · 7 answers · asked by xoxXaimless..Xxox 2

hi Chemists,
I need to know the nuclear composition for the following elements:
N:
F:
O:
C:

What the hell is nuclear element?! Cheers agus Slainte!

2007-05-20 07:56:55 · 4 answers · asked by philip c 1

how many moles of methane, CH4, would you need to produce enough hydrogen gas to produce 6 moles of ammonia, NH3?

2007-05-20 07:45:10 · 2 answers · asked by Thatdudenextdoor 3

I need to know soon. My formula doesn't make sense, so I'm thinking that it shouldn't react but for some reason I wrote down that it did..

2007-05-20 07:41:34 · 4 answers · asked by Jaclyn 1

2007-05-20 07:36:44 · 1 answers · asked by ALI L 1

A compound of sulfur and hydrogen was burned in oxygen to produce sulfur dioxide and water. The number of moles of sulfur dioxide produced was 1.5 times the number of moles of water produced. What is the empirical formula of the compound?

2007-05-20 07:34:25 · 1 answers · asked by Division12 2

how do you tell a strong acid from a weak acid ? and how do you tell a strong base to weak base? detailed plz

2007-05-20 07:29:18 · 4 answers · asked by Jennifer L 2

1) if 20.0g of magnesium react with excess hydrochloric acid, how many grams of magnesium chloride are produced?
Mg(s) + HCl ---> MgCl2(aq) + H2(g)

2) how many grams of chlorine gas must be reacted with excess sodium iodide if 10.0g of sodium chloride are needed?
NaI(aq) + Cl2(g) ---> NaCl(aq) + I2(s)

3) how many grams of oxygen are produced in the decomposition of 5.00 g of potassium chlorate?
KClO3(s) ----> KCl(s) + O2(g)

how do i do these types of problems? thank you very much

2007-05-20 07:18:17 · 2 answers · asked by =) 4

What is the oxidation number of chromium for each of CrS, CrPO4, Na2CrO4 compound? Answer in order like -2,+3,+4.(in order).

2007-05-20 07:16:43 · 1 answers · asked by Anonymous

balance and complete:
__CaO + __H2O ---->
__CO2 + __H2O ---->
__K2O + __H2O ---->
i dont get this **** and im outta this class in 5 days please have mercy lool

2007-05-20 06:33:10 · 2 answers · asked by stephy 1

Convert word equations into formula equations
Cesium hydroxide reacts with Copper(III) phosphate to produce Copper(III) hydroxide and Tricesium phosphate

conver the formula equation into a word equation
NaOH+H3PO4 >(hv) Na3PO4+H2O

Thanks for your help. If you can explain with answering it will be greatly appreciated

Determine the number of moles of the following
50.0 g SrSO4
25 L of Al(OH)3

Determine the mass of the following
2.0 moles of Al(OH)3

Determine the number of molecules
40 moles of H2

Determine the % composition
Al(OH)3

Solve the following problems using the appropriate gas law
Calculate the colume a gas that had originally occupied a 25 L at a pressure of 3.55 atm. And then the pressure on the gas increased to 405kPa
If 2.5 moles of gas is at a 258K and 35000 kPa what volume will it

2007-05-20 06:25:45 · 1 answers · asked by Holly B 2

2007-05-20 05:38:12 · 4 answers · asked by Anonymous

2007-05-20 05:31:47 · 2 answers · asked by Anonymous