Chemistry - April 2007

If a 4.20 lb cat absorbs 4.40 × 10−5 KJ of radiation, how many rads did this cat absorb?

2007-04-29 13:24:40 · 1 answers · asked by Anonymous

2007-04-29 13:11:45 · 1 answers · asked by Edua 1

How can you measure one liter of apple cider out of a barrel, if all you have available is a 3-liter and a 5-liter pitcher?

2007-04-29 12:53:53 · 1 answers · asked by Anonymous

A. Anions give up electrons.
B. Cations take up electrons.
C. Oxidation occurs at the anode.
D. Proton transfer occurs in the reactions.
E. Reduction occurs at the cathode.

Please explain why.

2007-04-29 12:02:01 · 1 answers · asked by Allie C 1

1) A buffer is prepared by dissolving 3.753g sodium acetate in 125.0mL of 0.1091M acetic acid. What is the pH of this buffer?

ALSO:

2) A 0.257g sample of solid acid is titrated with 40.05mL of 0.1121 M NaOH. This overshot the endpoint and 2.52ML of 0.0953 M HCl was used to back titrate. What is the equivalent mass of the acid?

2007-04-29 11:49:25 · 2 answers · asked by Anonymous

Given: 2cups flour + 3eggs+1tbs oil>>>4waffles

2007-04-29 11:44:29 · 3 answers · asked by dman 1

Given the following equation:
2Al(s) + 2KOH(aq) +6(H2O)[L] => 2KAl(OH)4[aq] +3(H2)[g]

If you place 2.05 g of aluminum in a beaker with 125-ml of 1.25 M KOH, will any aluminum remain? Show work and justify your answer so I can learn how to do this.

What mass of KAl(OH)4 is produced?

Thank you whoever helps solves this. I don't know how to solve these so show your work please. All the needed information to solve the problems is given.

2007-04-29 11:24:59 · 1 answers · asked by Anonymous

2007-04-29 11:24:21 · 1 answers · asked by redhotstiletoes<3 1

For the following reaction at 25 oC, ΔHo = -1008 kJ and ΔSo = 180 J/K

A +4B → 3C + 3D

What is ΔGo at 100 oC in kJ?

2007-04-29 10:55:38 · 2 answers · asked by lkatch 2

In a titration experiment it was found that a 50.00mL sample of H2SO4 was neutralized by 62.50mL of .375M NaOH. What is the molarity of the H2SO4 sample?

show work, please

2007-04-29 10:54:53 · 1 answers · asked by tpsurvey1986 1

Which has 10 protons?
A -1 ion of flourine.
A neutral atom of neon.
A +1 ion of sodium
All of these

please answer if ya know!
Thankyou!!

2007-04-29 10:52:48 · 5 answers · asked by Anonymous

I know you can use electrolysis to separate water into two compound elements, O2 and H2 both completely pure, but can you use electrolysis in other liquids???

2007-04-29 10:50:48 · 2 answers · asked by guille4ty 2

In each pair, which compound has the higher boiling point? ( the atomic numbers of the atom are: Ci, 17; S, 16; O, 8; C16; H, 1)

a) C2ci2h2 (1 chlorine atom on each carbon atom and on same side of molcule) vs. C2CI2H2 ( 1 chloride atom on each carbon atom and on opposite sides of molecule)

b) SCO vs. Co2

c) COCI2 vs. C2CI2H2 ( 2 chlorine atoms bounded to same carbon atom)

2007-04-29 10:50:23 · 2 answers · asked by Melissa H 1

Anything is appreciated, thanks

2007-04-29 10:50:19 · 1 answers · asked by fireflyspace23 3

Given data to find 1) the rate constant for the process 2) how long would it take for Yuck-1 decompose to its "safe" level of 0.06g

Time (hrs) 0 1 2 3 4 5 6
Mass remaining (g) 6.0 4.24 3.0 2.12 1.5 1.11 0.75

2007-04-29 10:47:39 · 1 answers · asked by azncrazygurl520 1

If iron(II) has a similar nature in water, will a 1.0 M solution of iron(II) nitrate have a higher or lower pH than a 1.0M solution of iron(III) nitrate?

2007-04-29 10:42:51 · 1 answers · asked by k m 1

occurred after 10 minutes?

2007-04-29 10:27:28 · 1 answers · asked by Anonymous

1. How would you prepare 500mL of 0.10mol/L copper II sulfate solution?

2. how would you prepare 25.0 mL of 2.5 mol/L iron III chloride solution?

2007-04-29 10:17:21 · 1 answers · asked by no name 1

Aqueous Fe(NO3)3 is slightly acidic as shown by the following equilibrium:

Fe(H2O)6 +3 (aq) + H2O <=> Fe(H2O)5(OH)+2 (aq) + H3O+

If iron(II) has a similar nature in water, will a 1.0 M solution of iron(II) nitrate have a higher or lower pH than a 1.0 M solution of iron(III) nitrate? Defend your response.

2007-04-29 09:47:33 · 1 answers · asked by k m 1

A mixture of N2(g) and O2(g) occupies 10 L at 250 K and 8000 mm Hg. All of the O2(g) is removed as P4O10(s) by reaction with P4(s) and the remaining N2(g) has a pressure of 250 mm Hg at 250 K. What mass of P4O10(s) is formed?

2007-04-29 09:31:36 · 1 answers · asked by jacque c 1

Would increasing the amount of O2 per liter increase this reaction's reaction rate? Would adding the catalyst I- to the system? Would changing the temperature to 35°C? What about increasing the amount of H2O2 per liter? Or increasing the pressure of the system?

2007-04-29 09:17:23 · 2 answers · asked by theweirdguy1 2

1) 0.75m (NH4)2SO4
2) 1.5m ethanol
3) 1.0m NaCl
4) 2.0m glucose
5) 1.0m CaSO4

a) which solution will have the lowest freezing point? explain
b) which solution will have the highest freezing point? explain

2007-04-29 09:14:23 · 1 answers · asked by azncrazygurl520 1

How to you find the oxidation half reaction and the reduction half reaction for these equations.

2H2 + O2 --> 2H2O

Cu + 2AgNO3 --> Cu(NO3)2 + 2Ag

2007-04-29 08:46:06 · 1 answers · asked by cookiemonstah 4

The number of nuclei decaying in a sample of Gallium-68 decreased by a factor of 4 over a period of 136.6 minutes. What is the half life of this isotope?

2007-04-29 08:29:16 · 3 answers · asked by Anonymous

If a 7.00 lb cat absorbs 2.30 × 10−4 KJ of radiation, how many rads did this cat absorb?

2007-04-29 08:06:58 · 1 answers · asked by Djuna 2

also, what's the reaction between sulfuric acid and sodium hydroxide?

2007-04-29 07:57:54 · 1 answers · asked by soccrrulz21 2

For a first order reaction the rate R = −k N so the ratio of rates at two different times is given by R(t1)/R(t2) = N(t1)/N(t2).
For nuclear decay the rate is ofen is expressed in units of counts per unit of time.

A chemists determines that a sample of petrified wood is 3.00 X 103 years old. What is the rate of decay, in counts per minute per gram, of carbon-14 in the sample? The decay rate of carbon-14 in wood today is 13.6 counts per minute per gram, and the half life of carbon-14 is 5730 years.

2007-04-29 07:24:27 · 1 answers · asked by Gemini 2

Hey I'm doing a chem lab on vinegar. I was wondering, if the bottle of vinegar says 5% acidity....what exactly does that mean? I know the acid in vinegar is acetic acid. So does the 5% acidity label on the box mean that 5% of the total mass of the vingegar is acetic acid? Or does it mean that 5% of the total volume is acetic acid? I don't really know =\ Can anyone please help? Basically for my lab I did an experiment to figure out the volume of NaOH i need to neutralize the Vinegar and now I need to figure out which of the two samples of vinegar i tested is the better choice. How would I decide this? I guess i need to figure out the % of acetic acid in the vinegar sample i used but even if i have the percents at the end which one would be the better one? The one closer to 5%?

2007-04-29 07:19:21 · 3 answers · asked by Anonymous

Are excited electrons more easily lost?

2007-04-29 07:13:03 · 5 answers · asked by howdy 2

2007-04-29 06:23:06 · 1 answers · asked by madan_023 1