Chemistry - January 2007

What factors would cause the percent yield to be HIGH? Select all that apply.


a. The recovered copper containing copper oxide from exposure to the air
b. Recovered copper being wet
c. The recovered copper containing unreacted zinc
d. Using too much nitric acid to react with the copper wire
e. Adding too much zinc to the copper(II) sulfate

2007-01-28 06:29:44 · 5 answers · asked by Anonymous

Why do atoms of Group 1 elements lose electrons to form cations, while atoms of Group 17 elements gain electrons to form anions?!

2007-01-28 06:17:52 · 4 answers · asked by Anonymous

2007-01-28 05:59:19 · 8 answers · asked by Anonymous

WHATS THE DIFFERENCE BETWEEN THEM?!

2007-01-28 05:56:48 · 5 answers · asked by Anonymous

how is Neodymium obtained and purified for common usage?

Thanks :)

2007-01-28 05:40:10 · 1 answers · asked by luckyplaya23 2

State the importance of valence electrons in the organization of the periodic table.

2007-01-28 05:39:30 · 4 answers · asked by Anonymous

crushed ice melts faster than cubed ice because?
a. there is more surface area of the crushed ice in contact with the air
b. there is less surface area of the crushed ice in contact with the air
c. the crushed ice has a higher temperature
d. the crushed ice has a lower temperature

2007-01-28 05:33:32 · 10 answers · asked by tico 1

I plan to conduct a demonstration lesson on stoichiometry using copper (II) sulfate which i plan to hydrate. Is it as simple as computing for the mass of the anhydrous and adding the mass of 5 moles of water?

2007-01-28 05:29:23 · 2 answers · asked by Marinela C 1

How is Russian gold used in plating jewlery?

2007-01-28 05:28:11 · 3 answers · asked by Vintage-Inspired 6

2007-01-28 05:20:45 · 3 answers · asked by Anonymous

1. Living matter has a carbon-14 activity of 16 counts/min per gram of carbon. What is the age of an artifact for which the carbon-14 activity is 8 counts/ min per gram of carbon

2007-01-28 05:18:52 · 3 answers · asked by Mia16 3

2007-01-28 05:16:25 · 4 answers · asked by Michael L 1

What is the relationship between the number of linked water molecules and temperature?

2007-01-28 05:00:52 · 1 answers · asked by :] 3

2007-01-28 04:57:30 · 8 answers · asked by HAWKEYE 2

2007-01-28 04:34:31 · 2 answers · asked by Anonymous

what is the chemical explanation to it.

2007-01-28 04:31:04 · 3 answers · asked by Anonymous

2007-01-28 04:28:52 · 1 answers · asked by Anonymous

Combustion of 7.51 mg of certain organic compound yields about 17.10 mg CO2 and 5.26 mg of H20. This compound contains only C, H, and O. What is the percentage of C in this substance?

i dont know what im doing wrong, i converted mg to grams and tried solving for the empirical formula of the compound but it didnt seem right

2007-01-28 04:13:46 · 1 answers · asked by gottalovkait 1

the enthalpy of fusion of ice is 6.02 kJ/mol. the heat of capacity of liquid water is 75.4 J/mol C. what is the smallest number of ice cubes at 0.0 C, each containing one mole of water, necessary to cool 750g of liquid water initially at 30C to 0.0C?

2007-01-28 03:27:04 · 1 answers · asked by mullen1120 1

Can anybody tell me the percentage amount of Potassium Citrate that is put into making Club Soda? The ingredient label on a bottle of Club Soda reads as follows: Carbonated Water, Potasium Bicarbonate and Potasium Citrate.

2007-01-28 03:19:35 · 1 answers · asked by evlme2 1

how can you keep your fish from spoiling between fresh catches if you were in a desrted island?

2007-01-28 03:03:34 · 4 answers · asked by nia 1

I have a question regarding the energy needed to raise an electron a level (from level 2 to level 3). I'm pretty sure you use the equation (E = -Rhc/n^2) but I'm not sure which number to put into the "n" value, and better yet, I'm getting an answer that isn't on the sheet for either using 2 or 3 for the n value! Is there something wrong w/ this equation or am I doing something wrong?

2007-01-28 02:56:19 · 2 answers · asked by Matt B 3

2007-01-28 02:41:03 · 7 answers · asked by TC 1

I need help understanding intermolecular forces and a lot of it has to do with whether it is nonpolar or polar and i need help understanding how to determine whether a molecule is polar or nonpolar is there a system like one is usually nonmetal w/ metal or something i thought i learned that before?

2007-01-28 02:03:32 · 2 answers · asked by imjustmewhatelseshouldibe 1

2007-01-28 02:01:11 · 1 answers · asked by Jayjay G 1

2007-01-28 01:37:25 · 4 answers · asked by Anonymous

example pls...

1. Cesium
2. Bromine

2007-01-28 01:36:06 · 1 answers · asked by Anonymous

2007-01-28 01:20:46 · 2 answers · asked by Anonymous

oC ?


The specific heat capacity of solid water is 2.03 J g-1 oC -1


Use a negative sign in your answer if heat is removed.

2007-01-28 01:09:36 · 5 answers · asked by Beth F 1

2007-01-27 23:30:56 · 2 answers · asked by amazing_sweet_angel 1