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DrBob
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I see that the Bot doesn't answer very some questions in chemistry correctly. Perhaps about 50% are incorrect. I have corrected
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Answers (109)
Hey Bot--In your equation you identify m as mass of the substance deposited. Did you substitute the mass or did you substitute the moles? Which should you have substituted?
Hey Bot. I think you calculated coulombs incorrectly as well as converting 1.5 hours to seconds incorrectly.
I don't think so. Mass = 2.0076 x 10^-2 kilograms or 0.0201 grams should be as follows: 2.0076 x 10^-2 kg x 1000 g/kg = 2.0076 x 10^-2 x 10^3 = 20 g
Hey Bot. This is what you posted. "Mass = 2.0076 x 10^-2 kilograms or 0.0201 grams" Did you make the conversion from kg to g correctly.
Hey Bot. I think your answer of 3.00 x 10^23 calculates the number of molecules of NH3 in the 8.5 g NH3. Is that correct? If so then you should multiply by 4 to obtain the number of items; i.e. there are 4 items in each molecule (1 N and 3 H atoms = 4
Hey Bot. You said "Number of carbon atoms = 6 (carbon atoms/molecule) * 0.0095 mol ≈ 0.057 carbon atoms" Didn't you mean Number of MOLES of carbon atoms = 6 (carbon atoms/molecule) * 0.0095 MOLS C6H12O6 ≈ 0.057 MOLES carbon atoms. Then shouldn't we see
Bot I don't see where you corrected for the 12 C atoms in sucrose.
Aren't the numbers 1027.8 g and 1023.2 g? I think the spaces are typos.
Bot, you did not use the numbers given in the problem for mass before and after the experiment.
Great. Looks good to me.
Bot, your definition still is incorrect. The definition of a 1.33 molal methanol solution means that you have 1.33 moles methanol in 1000 g water for a total mass (which is not needed to work the problem). The part of the problem you have wrong is that " A
No. A 1.33 molal solution means you have 1.33 moles methanol + 1000 g water and NOT 1000 g of SOLUTION. Therefore, there are 1.33 moles methanol + 55.5 mols water = 55.5 + 1.33 = 56.83 total moles. Xmethanol = mols methanol/total mols = 1.33/56.83 =
Bot, the problem states that the solution is 1.33 m in methanol; therefore, there must be 1.33 moles methanol and not what you calculated.
The correct answer is 5/4 x 32 = 40 grams O2 needed.
WOW. What a bunch of answers. The correct answer must be 1 cup sugar x (81 brownies/9 brownies) = 9 cups of sugar OR 9 brownies/1 cup sugar x ? cups sugar = 81 brownies ? cups sugar = 81/9 = 9 cups sugar OR (1 cup sugar/9 brownies) = (? cups sugar/81
It's one times the 6
The question makes no sense to me. Soluble in what? water? The answers don't make sense to me either. ZnCO3 is not soluble in water but ZnSO4 is soluble. However, what is zinc sulfate acid? MgCO3 is not soluble in water. MgSO4 is soluble in water.
Bot, I think your answer needs more work.
i don't get it. There are 32 cards from 2 through 9; therefore, there are 20 that are not numbered 2 through 9. 10, J, Q, K, A; i.e., 5 cards in each suit and 5 x 4 = 20 cards not numbered 2 through 9
please explain how there are 36 cards in the deck of 52 cards that are not numbered 2 through 9.
Thank you.
Bot, you have an error in the quadratic formula. You are correct to this point. x = (-1.75 x 10^-5 ± √[(1.75 x 10^-5)^2 - 4(1)(-4.375 x 10^-7)]) / (2(1)). However, in the next step it appears you have multiplied by an extra 4.375 x 10^-7; i.e. in the
Bot, I believe you made a math error in the quadratic formula. The equation you have of x^2 + 1.75 x 10^-5x - 4.375 x 10^-7 = 0 is correct but I have (OH^-) = approximately 0.00067 M which makes the pH = approximately 10.8. Check it out please.
I think your corrected answer still is incorrect. Bot, check out my response below. Do you agree or disagree. Starting with your equation of 6.3 x 10^-31 = 27x^4 x^4 = 6.3E-31/27 = 2.33E-32 x = (2.33E-32)^0.25 = 1.24E-8 M
I think you made another math error
Bot, did you make a math error?
Bot, you forgot to multiply by 2 to obtain F^-. CaF2(s) ⇌ Ca2+(aq) + 2F-(aq) solid..........2.6E-5.......2*2.6E-5 Ksp = (Ca^2+)(F^-)^2 = (2.6E-5)(5.2E-5)^2 Ksp = 7.03E-14
For the CH problem it the molar mass of the compound is listed as 78. Since CH is 12 + 1 = 13, then 78/13 = 6.0; therefore, the molecular formula is C6H6.
does that make sense to you? -3.8 is closer to zero than -4.5
Bot, your equation is wrong. There is no need to add H2O to the MnO4^- --> MnO4^= My equation, reposted below, is correct. 2MnO4^- + SO3^= + 2OH^- -----> 2MnO4^= + SO4^= + H2O
MnO4^-1 + SO3^2- → MnO4^2- + SO4^2- Divide into oxidation half and reduction half as follows: MnO4^- ==> MnO4^2- and SO3^2- ==> SO4^2- ================================== Balance each half MnO4^- + e ---> MnO4^= SO3^= + 2OH^- ----> SO4^= + 2e + H2O
still not balanced but closer. I'll do it right when I have time.
oxygen doesn't balance. charge doesn't balance. hydrogen doesn't balance. it isn't under basic conditions. the final equation may not have electrons.
The equation still is not balanced. I think there is a typo in the initial equation. Here is the original. MnO4^-1 + SO3^2- + 12 H+ + 6 e^- → Mn4O^2- + SO4^2- + 4 H2O I think the author meant to write the following: MnO4^-1 + SO3^2- → MnO4^2- + SO4^2-
Regarding the first question about water, 1 molecule of water + 1 molecule of water makes 2 molecules of water. There is no such thing as an atom of water. Regarding the equation, the solution by Bot does not balance the equation.
Incorrect. Yes, both AgNO3 and NH4Cl are soluble BUT not all chlorides are soluble; i.e. AgCl is not soluble;therefore AgCl will ppt and the reaction is AgNO3(aq) + NH4Cl(aq) ==> AgCl(s) + NH4NO3(aq) There is no reaction for the other one BECAUSE MgSO4 and
What does GPT3.5 and GPT4 mean
Bot, I believe there is a math error in the step below. I believe the correct ansewr is closer to 1.39 L V = (0.062 mol)(0.0821 L•atm/mol•K)(273 K) / 1 atm = 1.211 L
I assume that is 5.90 g MgCl2 produced. moles MgCl2 present in 5.90 g = grams MgCl2/molar mass MgCl2 = 5.90/95.2 = apprixunately 0.062. There are 0.062 mols MgCl2 x (6.022 x 10^23 molecules/1 mol) = approximately 3.7E22 molecles MgCl2. # Cl atoms =
Here is how to work the problem. Assume we take 1 mol Na2CO3.xH2O; thus we have 1 mol Na2CO3 and x moles H2O. mass Na2CO3.xH2O = approximately 268 from the problem. mass Na2CO3 = approximately 2(23) + 12 + 3(16) = approximately 106. Therefore, mass H2O =
still incorrect
Hey Bot. This is not the correct answer for x in Na2CO3.xH2O
Right! If X has a valency of +a and Y as a valency of -b. then the formula of the compound will be XbYa.
Bot, are you positive about that answer?
No, Bot is incorrect. The MOST volatile fraction contains the LEAST number of carbon atoms.
Of the choices listed the 2 is the best option, however, I usually refer to the valence of oxygen as 2-.
Bot is right. The correct name is magnesium sulfate. Technically, epsom salts is the heptahydrate of MgSO4.7H2O
and the correct name is magnesium sulfate
I believe 1.74 x 10^-5 is a better answer for 10^(-4.76) than 1.66 x 10^-5.
shouldn't the ratio of A^-/HA = 1 after the reaction?
