Chemistry - February 2007

trends in the physical properties of the elements accross a period and down a group(atomic radii boiling/melting point.ionisation of energies,types of struture)
trends in the chemical properties of the elements(metal/non metal,reactivity&reaction wih water
trends in the chemical properties of some compounds of the elements (reactivity and reations of the oxides with water

2007-02-23 22:22:38 · 4 answers · asked by Dany H 1

1 mL urine per minute__________gal/day?

2007-02-23 22:02:31 · 2 answers · asked by Anonymous

please..i need help...THANK YOU!

2007-02-23 21:57:41 · 2 answers · asked by Sofia 1

using aluminium oxide as a catalyst ???

2007-02-23 21:37:49 · 2 answers · asked by sugar 3

2007-02-23 21:19:34 · 1 answers · asked by Vijay S 1

Is it true that colloidal solutions have charged particles as solute particles?or, is it a suspension?Im confused....

2007-02-23 21:08:52 · 4 answers · asked by Anonymous

Liquid bromine placed in a gas jar for one hour will diffuse throughout the jar. Explain what happens to the liquid bromine in terms of particles.

2007-02-23 21:07:29 · 2 answers · asked by Anonymous

2007-02-23 21:01:01 · 2 answers · asked by Rajchem 2

2007-02-23 20:49:01 · 4 answers · asked by Anonymous

i.e what are periods,what are group?atomic number;electronic structures

2007-02-23 20:36:21 · 2 answers · asked by Dany H 1

Or is a colloid a type of solution? Thanks a lot.

2007-02-23 20:07:59 · 2 answers · asked by kmm4864990 1

homework experiment

2007-02-23 18:18:17 · 5 answers · asked by dian 2

chemistry hw.. experiment

2007-02-23 18:15:53 · 2 answers · asked by dian 2

A) its temperature deacreases
B)its temperature increases
C)it absorbs heat
D)It gives off heat

2007-02-23 17:59:06 · 4 answers · asked by DARNELL B 1

i hav my exams next week and i dnt knw how to find the coordiantaon number , pls hlp me , pls suggest if there is any formula or shortcut , pls help me [K4[Fe(CN)6] pls help me in finding the coordination number of this compound?

2007-02-23 17:20:53 · 1 answers · asked by Anonymous

2007-02-23 17:16:41 · 1 answers · asked by Carlos H 1

2007-02-23 17:13:49 · 1 answers · asked by piyushdravid 1

2007-02-23 17:12:30 · 5 answers · asked by Carlos H 1

2007-02-23 17:08:50 · 7 answers · asked by Carlos H 1

For every element, less energy is needed to remove an electron from a neutral atom than is needed to remove another electron from the resultant ion. Explain why..

2007-02-23 17:08:26 · 1 answers · asked by enigma 1

2007-02-23 16:57:38 · 1 answers · asked by anaisha j 1

Explain in terms of the kinetic particle theory

2007-02-23 16:52:00 · 3 answers · asked by Spector 1

who found this metal? what year is it?
where ?

2007-02-23 16:51:29 · 1 answers · asked by super_genuislau 1

Explain in terms of the kinetic particle theory

2007-02-23 16:49:25 · 3 answers · asked by Spector 1

if...
Solid X is soluble in both hot water and cold water
Solid Y is soluble in hot water but not in cold water
Solid Z is insoluble in hot and cold water

how would you seperate 'Solid Y' from a mixture of X, Y and Z.

2007-02-23 16:35:41 · 1 answers · asked by Anonymous

2007-02-23 16:21:50 · 2 answers · asked by wordonda 1

im so confsed on this... i would like no know how to set up proportions to solve her...

1.) C12H22011 (sucrose) + 302 ---> 2H3C6H5O7 + 3H20
H3C6H5O7 = Citric Acid
Determine the mass of citric acid produced when 2.50 mol C12H22011 is produced.

2.) Determine the amount of ethyl butanote produced ig 4.50 mol ethanol is used.
C2H5OH + C3H7COOH -----> NC3H7COOC2H5 + H20
(ethyl butanote = C3H7COOC2H5) (alcohol ethanol= C2 H5OH)
(butanic acid C3H7COOH)
Determine the mass if ethyl butanoate produced if 4.50 mol of ethanol is used.

***** i would really appreciate if you could explain to me the SET UP of these problems so i can try to figure them out. thanks so much.

2007-02-23 16:21:48 · 3 answers · asked by Anonymous

2007-02-23 16:18:43 · 4 answers · asked by shadib2003 1

2007-02-23 15:56:29 · 3 answers · asked by zyrzh_5 1

1. The new substances produced in a chemical reaction have________.
a. the same properties as the original substances.
b. different physical properties from the original substances.
c. different chemical properties from the original substances.
d. different physical and chemical properties from the original substances.

2. which reaction requires a continuous supply of energy?
a. an exothermic reaction
b. an endothermic reaction
c. a synthesis reaction
d. a decomposition reaction

3. when reactant paticles collide more ofter,
a. the reaction rate remains the same.
b. the reaction rate decreases.
c. the reaction rate increases.
d. None of the above.

4. Which of the following is an example of an exothermic reaction?
a. light energy is released in light sticks.
b. electrical energy is released in the dry cells of a flashlight.
c. light and thermal energy are released in a campfire.
d. all of the above.

2007-02-23 15:37:47 · 1 answers · asked by jennifer 1