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DrBob222
Answers (436)
We can't help if you don't post a question.
I can't help if you don't post a question.
I can't help if you don't post a question.
SAT stands for scholastic aptitude test. It is used, along with GPA and perhaps other criteria to determine a student's readiness for college. It is a requirement for entrance into many colleges and universities in the U. S. You can get more information by
q = dH = mass x specific heat H2O x delta T q = 50 g x 4.184 J/g*C x 5 = 1046 J That's 1046 J for 6.3 g NH4NO3. Convert that to J/mol Post your work if you get stuck.
2C4H10 + 13O2 ==> 8CO2 + 10H2O moles C4H10 in 10 L = 10/22.4 = 0.446 0.446 moles C4H10 x (10 mols H2O/2 mols C4H10) = 0.446 x 5 = ?
Let me see if I can rewrite the question to make better sense. What mass of Pb(NO3)2 would be required to produce 9g of PbCl2 upon the addition of excess sodium chloride solution? I think that is what you're asking. Pb(NO3)2 + 2NaCl ==> PbCl2 + 2NaNO3 I've
oops, I hit the wrong button. Ti has isotopes of 46, 47, 48, 49, 50. Perhaps I've trashed the problem incorrectly. I see the problem DID show a number for Ti as 48 and no one would argue with rounding C to 12.00 from 12.01. Sorry about that. It's easy to
I must say that I don't think this a very good question. 1. Carbon isn't exactly 12 and Ti isn't exactly 48 so none of the choices is correct unless you're rounding the number to 12 and 48. 2. Nothing is mentioned about isotopes. WHICH C isotope is being
There is nothing like a good ol' pesky decimal point.
oops. When you INCREASE the pressure the volume DECREASES. The other relationship is direct. In direct one variable goes up the other goes up. Or one goes down the other goes down. Of course some don't have a relationship; i.e., one variable goes up or
one variable goes up and the other variable goes down. Pressure-volume is inverse. When you INCREASE
You need to learn to do these yourself. Post your equation, tell us what you don't understand, and let us help you do it yourself.
Here is my personal opinion. I can't find anything especially wrong with what you've said; however, I don't think it is a good explanation. In my opinion you have simply rephrased the question and called that your answer. If I were grading your paper I
I'm sorry but I don't understand the question, particularly the portion " only 58.5% of it becomes originally". 58.5% becomes what? Please rephrase and repost.
I can't decipher this problem, particularly the "if 2343cm3 of a neutrized 25.0 cm3 of 13". Part A is 7.3 g HCl/dm^3 mols = g/molar mass = 7.3 g/36.5 = 0.2 mols/dm^3 When you repost please make sure that 2343 cc is correct. It seems large to me. Perhaps a
1.593e8 gallons x 1 hr/2000 gallon x (1 day/24 hr) = 3319 days. 489*43560 ft^3 * 7.48gal/ft^3 * 1hr/20000gal * 1day/24hr = 331.938 days oobleck made a typo and entered 20,000 gallons/hr and not 2000 gallons/hr so his corrected answer is 3319 days also.
I got the same numbers but just multiplied the previous number by 2. 2*2 = 4 4*2 = 8 8*2 = 16 16*2 = 32 32*2 = 64 etc.
Fe^3+ + NaOH ==> Fe(OH)3(ppt) + Na^+
I asked Google to convert 489 acre-feet to gallons and Google came up with 1.593e+8 gallons. So 1.593e8 gallons x 1 hr/2000 gallon x (1 day/24 hr) = ? days. BTW this look much more like a math problem than a chemistry problem. oobleck should check this
ditto
(I’m very confused and my teacher doesn’t help me). I could help more if I knew what was confusing you. Some detail about what is causing the problem. As it is I'm flying in the blind. So I'll give the answer, reluctantly, but please follow up and tell
P1V1 = P2V2 P1 = 2.94 Atm V1 = 0.026 mL P2 = 1.00 atm V2 = ? Solve for V2
The molar volume of a gas @ STP is 22.4 L/mol. The molar volume of a gas @ RTP (room temperature and pressure) is 24 L/mol. Room temperature is considered 20 Celsius. Standard pressure after 1982 is 1 bar but most in the U. S. use 1 atm.
FeCl3 + 3NaOH ==> Fe(OH)3 + 3NaCl
I am assuming this is an aqueous solution of CaBr2. Hydrogen gas is evolved at the cathode (the negative electrode) and Br2 is evolved at the anode (the positive electrode).
1. The equation as written is not correct. The proper way to write the equation is 2H2 + O2 ==> 2H2O 2. The question you've asked can't be answered BECAUSE you don't say how much hydrogen and how much oxygen are used. 3. However, I think I know what you
I don't see any values. Furthermore, none will reach zero although sevral may become VERY VERY SMALL. Often we call those very very small values as "essentially zero".
Ca + Cl2 ==> CaCl2 Look at the coefficients in the balanced equation. 1 mol Cl2 forms 1 mol CaCl2; therefore, 5 mols Cl2 will form 5 moles CaCl2. Then moles CaCl2 x molar mass CaCl2 = grams CaCl2.
I didn't do the math but your process is on the mark. Good work.
When you say dissolved you need to understand that I2 will not dissolve. Small amounts will but most of the I2 will remain solid. If the "solution" (and I use the term loosely) is allowed to evaporate under room conditions, you will end up with NaCl solid
Place a piece of glass in the fridge until it is cooled. Remove from the fridge, exhale onto the cool glass. Observe the droplets of water that have condensed on the cooled glass suface. You want to do this on a day when the humidity is low. This is not
(P1V1/T1) = (P2V2/T2) P1 = 760 mm Hg V1 = 800 cc T1 = 273 K P2 = 675 mm Hg V2 = 940 cc T2 = ? K T2 will be in degrees K. If you want degree celsius it will be K = 273 + C.
6 ug/uL x 20,000 uL = ? ug of the compound. Then convert ug to mg. or 6 ug/uL x 20 mL x (1000 uL/mL) x (1 mg/1000 ug) = ? mg.
You can look up the meaning of humidity in a dictionary.
I don't see a question.
I don't see any following.
Not my field either but I think D is the most likely correct choice.
You should learn to name this compound properly. It is hydrated sodium carbonate. Na2CO3 + 2HCl ==> 2NaCl + H2O + CO2. That's the equation. You can determine the x in the hydrate if you wish. millimoles HCl = mL x M = 13.20 mL x 0.16 M = 2.11)rounded)
Depends upon how much of much of that Sn is mixed with the Cu.
Not to be nit picky (I REALLY don't want to be nit picky) but some would argue that sulfur is S8 and the molar mass is 32.06*8 or 256.48. Frankly, although I agree sulfur actually is S8, I think that just complicates stoichiometry problems because it makes
This is not my field but I would go with D since spider webs are composed of protein chains and hydrogen bonds (intermolecular forces) and kevlar is polyamide chains and hydrogen bonds.
Most, if not all, of this banning talk is misunderstood. If you are posting you aren't banned.
How about "HELP"
Oxalic acid is H2C2O4. 1 gram equivalent is molar mass/2 = 90/2 = 45 but I've used rounded numbers. You can look up the atomic mass of each element and get a more exact answer than 45. Then 1.8909 g/45 = ? (use your better value of 45 here).
I see no image.
It is easier for the "sea of electrons" in Al to move. But Ca still is a conductor.
1. How long it takes a river to carve out a gorge.
B has one result but no comparison; i.e., better than what? C tests temperature which isn't what Evan wants to test. D has nothing about dark. A is the only one that tests dark vs light to give a comparison as to which is best. (actually which is
Definitely NOT. Look it up on Google. For example, melting ice. Start at -5 C. Heat must be added and the temperature of the ice cube will increase until the internal temperature reaches 0 C. At that point the ice crystal bonds begin to break and the first
