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which of these substances dissolve in water? and are they elements or compounds? copper nitrate sodium hydroxide copper hydroxide copper oxide hydrochloric acid aluminum copper chloride hydrochloric acid

18 years ago

A planet has two satellite moons. Moon X has an orbital period of 2.27 days. Moon Y has an orbital period of about 3.40 days. Both moons have nearly circular orbits. Use Kepler's third law to find the distance of each satellite from the planet's center. T...

15 years ago

As shown in the figure, a square has sides of 8.0 cm with a charge of +6.0 µC at one corner (a) and with charges of -2.0 µC at the remaining three corners (b, c, and d). The figure is just a square with no measurements. Corner a being the top left corner,...

15 years ago

How can i rearrange this Clausius-Clapeyron equation so that 1/T2 is on one side? In P2/P1=delta H vaporization/R (1/T2- 1/T1) I am trying to find at At what temperature does acetone have Pvap= 111 mm Hg. Acetone, a common laboratory solvent, has Delta H...

15 years ago

If 0.380 mol of a nonvolatile nonelectrolyte are dissolved in 3.00 mol of water, what is the vapor pressure P(H2O) of the resulting solution? The vapor pressure of pure water is 23.8 torr at 25 C. I got this answer correct: 21.1 torr A solution is compose...

15 years ago

Acetone, C3H6O, and ethyl acetate, C4H8O2, are organic liquids often used as solvents. At 30 degrees C, the vapor pressure of acetone is 285 mm Hg and the vapor pressure of ethyl acetate is 118mm Hg. the solution is prepared at 30 degrees C by dissolving...

15 years ago

If 49 m of nichrome wire is to have a resistance of 13.0 ohms at 20°C, what diameter wire should be used? I've done this: (108e-8)(49)/10.0 ohms = 5.29e-6m^2 Then 5.29e-6m^2/pi then r = sqrt(1.68e-6m^2) and got .00129 = 1.29e-3 1.29mm r=2(1.29mm) = 2.58mm...

15 years ago

At 100 degrees C , a certain substance undergoes second-order decomposition with a half-life of 26 minutes. If the initial concentration of the substance is 3.9×10−2M , what is the value of the rate constant at 100degrees C? So I put in (1560seconds) 1/2...

15 years ago

An old refracting telescope in a museum is 44.0 cm long and the caption states that the telescope magnifies images by a factor of 29.0. Assuming these numbers are for viewing an object an infinite distance away with minimum eyestrain, what is the focal le...

14 years ago

A beam of yellow laser light (590 nm) passes through a circular aperture of diameter 5.0 mm. What is the angular width of the central diffraction maximum formed on a screen? I can't seem to get this answer right. I don't think I am finding the first part...

14 years ago

I can't get the right answer, where am I going wrong? 7.0x10^9= (6.7x10^9)(2.72^r*3) 1.04 = 2.72^r*3 When I solve for this, I get ln (1.40) = 0.03922 then 0.03922 / 3 = 0.0130 So my r equals 0.0130 BUT the teacher says the answer is 0.05 = r *3 0.02 = r W...

14 years ago

Still couldn't get the correct answer :[

15 years ago

Thank you very much!

15 years ago

i got the mole fraction of cyclohexane in the solution but that isn't what it wants and I don't know exactly what the question is asking for. Can someone please explain to me how to do this problem?

15 years ago

I see where i went wrong. I was trying to take the mole fraction (.405) and divide it into the 176. Thank you.

15 years ago

When I did that I got this: 2.6 for acetone mole fraction 1.4 for ethyl acetate mole fraction 119 acetate vapor 30 ethyl acetate vapor None of those answers were correct. :[

15 years ago

Ooo. Gosh, I must have just been looking at the wrong number or something. I feel silly now.

15 years ago

2.27mm is the new answer I got, which is correct. Thanks for pointing that out, Bob. I was going insane trying to figure this out.

15 years ago

You are most correct, I did not. Thank you so much.

15 years ago

Actually, those answers are incorrect.

14 years ago

I just tried the problem with 1.22 and i got -1.21 as my final angular width. However, this is also incorrect. any ideas where I am going wrong?

14 years ago

I have also tried using the positive of the angular width. But that is wrong, too. I used the same equation as i did above but with the 1.22

14 years ago

The causes of Sand Creek massacre were rooted in the decades-long conflict for control of the Great Plains of eastern Colorado. The Fort Laramie Treaty of 1851 guaranteed ownership of the area north of the Arkansas River to the Nebraska border to the Chey...

14 years ago

Well, that was a step my teacher did so I just followed it. However, .00082 degrees is not the correct answer either (or the variant of 8.2e-4). So I am just totally lost on this one. :/

14 years ago

No. The math he did was handwritten. I guess he must have made a mistake because this is driving me nuts. Everything listed in my post is CORRECTLY copied from the piece of paper I got it on.

14 years ago

Bob, thank you. I thought I was going insane there for a minute. I guess the professor made a mistake. We are all human (but it drives me crazy when I'm trying to study haha)

14 years ago

14

3 years ago