Chemistry - December 2006

Certain elements frequently form ions with a 2+ charge. Where are these elements located on the periodic table?. What are they called and why do they form that kind of ion?.

2006-12-22 12:34:28 · 4 answers · asked by chemistrystudentinneed 1

Write a balanced equation for the decomposition of mercury (II) oxide.

2006-12-22 12:32:58 · 6 answers · asked by chemistrystudentinneed 1

In a lab experiment, you added sodium metal to aluminum oxide. Write a balanced equation for this experiment and predict whether or not a reaction will occur.


Benzene (C6H6) is a common industrial solvent. Write a balanced equation for the combustion of benzene in oxygen. Assume that the combustion is complete.

2006-12-22 12:31:00 · 4 answers · asked by kittyvamptress 2

a fixture in your house with a facet and a drain?
wholenium X 0.5?
someone who helps people in distress is a good___
after successfully riding a bronco a rancher shouts, "___"
burial chamber that weighs 2000 pounds?
boards that have been nailed down to walk on?
person from norway, sweden, or finland?
MUST BE A REAL ELEMENT from the periodic table of elements

2006-12-22 12:04:03 · 4 answers · asked by FrancetichSketch 3

13.Use this reaction for the following questions: CI(g)+2HBr(aq) ------2HCI(aq)+Br2(I)
a.Determine the oxidation numbers of each element in both the reactants and the products of this oxidation reduction reaction of chlorine and bromic acid.(6 points).
b.Which element is oxidized in this reaction?(2 points)
c.Which element is reduced in the reaction? (2 points).

2006-12-22 10:54:26 · 5 answers · asked by kittyvamptress 2

14.Ammonium sulfate,(NH4)2SO4,is a common ingredient in fertilizers and is a source of nitrogen.
a.Would you calculate the atomic mass, molecular mass, or formula mass of ammonium surfate? Explain how you came to your decision.
b.What is this value for (NH4)2SO4?
c.Avogadro’s number is equal to 6.0221x10 23. How may ammonium ions are in 100.0g of ammonium sulfate?
d.You make a solution of ammonium sulfate by mixing 150 g of(NH4)2SO4 in 2.00 L of water in a beaker. What is the molariry of the resulting solution assuming that all of the solute dissolves?

2006-12-22 10:47:37 · 2 answers · asked by kittyvamptress 2

15.A 0.200 L solution of .950M hydrochloric acid is used to neutralize a 10.0 g sample of calcium hydroxide in a coffee-cup calorimeter. Calcium hydroxide solution is known as slaked lime and is used in agriculture to “sweeten” acidic soils. The temperature in the calorimieter was observed to rise from 20.0*Cto29.2*C during the course of the neutralization. Assume that the density of the hydrochloric acid solution is 1.00g/mL and that the specific heat capacity of the system is the same as that for water,4.18J/g-K.Assume that only the water is available to absorb or release heat and that the reaction is at constant pressure.
2HCI(aq)+Ca(OH)2(aq)------CaCI2(aq)+2H20(I)
a.What was the limiting reagent in the neutralization reaction? Provide support for your answer.
b.How many moles of excess reagent were left over?
c.If 5.1 g of calcium chloride were obtained after the neutralization was complete, what was the percent yield?
d.What was the enthalpy change for the system in the coffee-cup calorimeter?
e.What was the heat of reaction per mole of water produced for the neutrailization reaction?

2006-12-22 10:34:38 · 3 answers · asked by kittyvamptress 2

2006-12-22 10:23:05 · 3 answers · asked by iheartyoumorethanbunnyz 1

2006-12-22 10:17:54 · 11 answers · asked by ♫ 2

What is the best graduation of a cylinder to measure medium volumes...
It needs to be a cylinder with small graduations (measurment between each mark on the cylinder)

Pleasssssse Help
Tthanks

2006-12-22 10:16:20 · 3 answers · asked by daniel4joyce 2

2006-12-22 10:08:03 · 6 answers · asked by kennychen 2

Iron metal is recovered from passing carbon monoxide over teh iron ore (Iron III Oxide) forming carbon dioxide and iron metal

Balance teh reaction equation
it would be Fe2O3--->CO+Fe???

When 116 g of CO reacts with excess Fe2O3, how many moles of Iron metal is recovered with a theorectical yield
116 divided by number of moles of Fe2O3 times 100 to get theorectical yield

If the process is not efficient, only 80% yield of Fe is recovered. How many grams would you recover from 116 gm of CO.
116 times 80% to get number of grams

2006-12-22 10:04:02 · 3 answers · asked by silentcargo 3

I'm trying to make a chemical garden, and I was wondering about how many mL of water should be added to 100 mL of sodium silicate. Would 400 mL be acceptable? Any help would be appreciated.

2006-12-22 10:02:17 · 1 answers · asked by Anonymous

2006-12-22 09:58:17 · 3 answers · asked by Chris S 1

2006-12-22 09:53:39 · 5 answers · asked by dopepink 1

A buffer solution of baking soda and washing soda was added to water and diluted. The pH was tested at approx. 10 on universal pH paper. Household ammonia and vinegar were added in separate buffer solutions and no pH changes were noted.

What ions were present in the buffer solution? Identify the weak acid and its conjugate base.

Thanks for your help.

2006-12-22 08:57:32 · 5 answers · asked by luc_allmon 2

2006-12-22 07:22:45 · 16 answers · asked by Anonymous

2006-12-22 07:20:05 · 6 answers · asked by Randy M 1

1.) Na + H2O ----> NaOH + H2
2.) Na2B4O7 + HCl + H2O ----> H3BO3 + NaCl
3.) Fe2(SO4)3 + Ba(OH)2 ----> Fe(OH)3 + BaSO4
4.) C12H22O11 + H2O ----> C2H5OH + CO2


i just cant balance them. all the numbers are subscripts

2006-12-22 06:48:04 · 12 answers · asked by Pearl 2

AN OBJECT

2006-12-22 06:44:18 · 2 answers · asked by chanti 3

The molar mass of Fe2(SO4)3 is 399.91 g/mol. How do you figure this stuff out?

2006-12-22 06:44:07 · 5 answers · asked by sydney 2

Gold atom=how many neutrons

2006-12-22 06:23:05 · 5 answers · asked by Anonymous

2006-12-22 06:13:34 · 5 answers · asked by Anonymous

2006-12-22 06:12:34 · 3 answers · asked by Anonymous

2006-12-22 06:08:12 · 3 answers · asked by Anonymous

An unknown gas is placed in a 2.5L vessel at a pressure of 400 mm Hg and a temp of 45C and weighs .834g.

2006-12-22 05:56:19 · 5 answers · asked by janeeyre444 1

2006-12-22 05:54:22 · 2 answers · asked by janeeyre444 1

2006-12-22 05:52:55 · 3 answers · asked by janeeyre444 1

2006-12-22 05:51:09 · 3 answers · asked by janeeyre444 1

2006-12-22 05:49:50 · 2 answers · asked by janeeyre444 1