Chemistry - December 2007

N P
hydrogen-2 (atomic number=1)

n stands for neutrons
p stands for protons

2007-12-09 07:11:40 · 2 answers · asked by Too CooL 3

Consider the combustion reaction between 30.0 mL of liquid methanol (density = 0.850 g/ mL) and 15.0 L of oxygen gas measured at STP. The products of the reaction are CO2 (gas) and H20 (gas)

2007-12-09 07:11:11 · 2 answers · asked by plastickfourk 1

This is supposed to be a single displacement reaction, and there was a forming of copper.

But the solution is supposed to be magnesium chloride, which is supposed to be colourless and transparent.

Instead, the solution formed in our experiment was light green and opaque. What happened?

2007-12-09 07:09:05 · 1 answers · asked by Teressa 1

Assuming the following reaction proceeds in the forward direction,

Ni2+(aq) + Cr(s) → Ni(s) + Cr2+(aq)

a.Ni(s) is oxidized and Ni2+(aq) is reduced.
b.Ni2+(aq) is oxidized and Cr(s) is reduced.
c.Cr(s) is oxidized and Cr2+(aq) is reduced.
d.Ni2+(aq) is oxidized and Ni(s) is reduced.
e.Cr(s) is oxidized and Ni2+(aq) is reduced

2007-12-09 07:03:56 · 2 answers · asked by Anonymous

which isotope, when is bombarded with oxygen-18, yields the artificial isotope seaborgium-263 plus 4 neutrons?

1. nobelium-245
2. radium-259
3. californium-245
4. nobelium-249
5. californium-249

2007-12-09 07:03:47 · 1 answers · asked by Daone 1

Use the standard reduction potentials below to determine which element or ion is the best oxidizing agent.

Br2(λ) + 2 e- → 2 Br-(aq) E° = +1.08 V
Hg2+(aq) + e- → Hg(λ) E° = +0.86 V
Ni2+(aq) + 2 e- → Ni(s) E° = -0.25 V

a.Br-
b.Ni2+
c.Ni
d.Hg2+
e.Br2

2007-12-09 06:55:13 · 4 answers · asked by Anonymous

LIke what causes them to produce gases and what may those gases be?

2007-12-09 06:53:01 · 2 answers · asked by Marla I 1

2007-12-09 06:51:47 · 1 answers · asked by maria g 1

It's for a project. I have the common ones like burning wood, candle, gas and baking i just need one more!
thanks.

2007-12-09 06:50:12 · 7 answers · asked by Anonymous

do all atoms have protons and neutrons

2007-12-09 06:47:27 · 3 answers · asked by Yasir Ali 3

Calculate the E°cell for the reaction below,
Tl+(aq) + 2 Cl-(aq) → 2 Tl(s) + Cl2(g)

given the following standard reduction potentials.

Cl2(g) + 2 e- → 2 Cl-(aq) E° = +1.36 V
Tl+(aq) + e- → Tl(s) E° = -0.34 V

a.-2.04 V
b.+1.70 V
c.+2.04 V
d.1.02 V
e.-1.70 V

2007-12-09 06:46:29 · 1 answers · asked by Anonymous

The difference between the third and fourth ionization energies of scandium is much larger than the difference between the third and fourth ionization for titanuim. Why???

2007-12-09 06:37:31 · 2 answers · asked by John 3

In the following reaction,

2 Fe3+(aq) + Zn(s) → 2 Fe2+(aq) + Zn2+(aq)

a.Zn(s) is the reducing agent and Fe2+(aq) is the oxidizing agent.

b.Zn(s) is the reducing agent and Zn2+(aq) is the oxidizing agent.

c.Fe3+(aq) is the reducing agent and Zn(s) is the oxidizing agent.

d.Zn(s) is the reducing agent and Fe3+(aq) is the oxidizing agent.

e.Fe3+(aq) is the reducing agent and Fe2+(aq) is the oxidizing agent.

2007-12-09 06:36:44 · 4 answers · asked by Anonymous

In which of the following substances is hydrogen bonding likely to play an important role in determining physical properties and why: Methane (Ch4), Hydrazine(H2NNH2), Methyl Fluoride (Ch3F) or Hydrogen Sulfide(H2S) ?? And why??

Thanks in advance

2007-12-09 06:30:43 · 2 answers · asked by John 3

In which of the following statements is the functional group correctly identifed for the given compound ?


a) CH3CH2CH2COH ether


b) H3CCOCH3 ketone


c) CH3COOCH2CH3 ketone


d) C6H5CN nitrile

there can be more than one correct answer

2007-12-09 06:30:35 · 1 answers · asked by Anonymous

It has gone into the floor boards. How can I remove it or what can I use on the wood to neutralise it? I think it leaked as a vapour rather than a spillage.

2007-12-09 06:28:38 · 3 answers · asked by Anonymous

25.0 mL of 0.10 M iron (III) nitrate with excess sodium hydroxide?

2007-12-09 06:22:46 · 3 answers · asked by Blah 1

22) The Second Law of Thermodynamics states that in spontaneous reactions, the universe tends toward a state of greater disorder. When the entropy increase in the system is greater than the entropy decrese in the surroundings, the entropy of the universe will increase.
A) a release of heat by the system
B) an absorption of heat by the system
C) an increase in disorder in the system
D) a decrease in randomness in the system
E) none of the above

16) A 73 g sample of water with a temperature of 5.3°C is added to 271 g water at 59°C in an insulated container. What is the final temperature after thermal equilibrium is reached?
A) 0.021°C
B) 17°C
C) 32°C
D) 48°C
E) 224°C

2007-12-09 06:18:48 · 1 answers · asked by lyudmila y 1

Hi can someone please help me with some similarities and some differences between San Le's periodic table and the normal periodic table?

2007-12-09 06:09:51 · 1 answers · asked by kyle v 1

What increase in the Celsius temperature will produce a 7.0% increase in the volume of a sample of gas originally at 25.0°C if the gas pressure is held constant?

2007-12-09 06:06:48 · 2 answers · asked by Donna L 3

At high temperatures we see trees combust and turn to ash, but is it possible for the temperature to rise high enough that the bark and all the other parts of a tree would turn to liquid? If not, why not?

2007-12-09 05:58:57 · 5 answers · asked by ancient_egyptian_laser_beams 2

Please show work and use significant figures?

2007-12-09 05:50:44 · 4 answers · asked by jkk04 3

A gas has a presure of 0.370 atm at 50.0°C. What is the pressure at standard temperature?

2007-12-09 05:45:45 · 2 answers · asked by lismithly 2

13. A container holds 3 gases: oxygen, carbon dioxide, and helium. The partial presure of the three gases are 2.00 atm, 3.00 atm, and 4.00 atm, respectively.
What is the total pressure inside the container?

Please show work and use significant figures.

2007-12-09 05:45:06 · 3 answers · asked by lismithly 2

Some of the best laboratory vacuum systems can pump down to as few as 1.0 109 molecules per cubic meter of gas. Calculate the corresponding pressure, in atmospheres, assuming a temperature of 25°C.
____________atm

2007-12-09 05:36:42 · 1 answers · asked by Donna L 3

8. A balloon has a volume of 2500.0 ml on a day when the temp is 30.0°C. If the temperature at night falls to 10.0°C, what will be the volume of hte balloon if the pressure remains constant?

2007-12-09 04:56:08 · 3 answers · asked by Lorr C 1

90Sr38→ 90Y39+ ?
proton
beta particle
neutron
alpha particle
gamma ray

2007-12-09 04:52:21 · 3 answers · asked by sonia 1

i would also like to know if it can be produced by reacting aluminium with lime ...if so how ?? i would like to know the method in detail...

2007-12-09 02:22:16 · 4 answers · asked by enigma 1

Solving 1 or both of them is fine, as long as explanation is included.

1. An impure sample of Na2SO4 has a mass of 1.56 grams. This sample is dissolved and allowed to react with BaCl2 solution. The precipitate has a mass of 2.15g. Calculate the percentage of Na2SO4.

2. An impure sample of Na2SO4 has a mass of 1.65g and is dissolved in water. Addition of BaCl2 solution produced a precipitate of barium sulphate with mass 2.32g. What is the percentage of NaCl in the mixture?

2007-12-09 01:11:51 · 5 answers · asked by onlineworld 1

For example: A substance contains 10% X 18.7% Y and 71.3% Z (XYandZ being the elements) what is the empirical formula? I chose not to write the actual question cause this is homework and I don't wanna cheat.

2007-12-09 01:03:46 · 2 answers · asked by Ethereal 4