check

  1. C

    Check the task please

    Check the task please 1. The reaction speed the equation of which is Fe+H2SO4=FeSO4+H2↑will be the highest when we use a) Fe granules and 0.1%-solution of H2SO4 b) Fe powder and 10%-solution of H2SO4 c) Fe granules and 10%-solution of H2SO4 d) Fe powder and 0.1%-solution H2SO4 My answer is b).
  2. C

    Please check the tasks

    Please check the tasks 1. Calculate the volume of ethanol (with a density of 0.8 g / ml and a mass fraction of 80%) and the volume of water needed to prepare 1000 ml of 0,2-molar C2H5OH). 2. Calculate the mass of sodium chloride and the volume of water needed to prepare 200 g of 1-molar...
  3. C

    Check please

    17.4 g of K2SO4 contain in 200 ml of the solution. Calculate the molar salt concentration in the solution. Please check the decision c=m/(M*ν)=17,4/(174*0,2)=5 mol/L
  4. M

    double check a chemistry answer

    I found this question online, I am being asked the exact question for an assignment however I don't know if it is right. The reason for this, is that when I try to calculate the percentage error it gives me an unrealistic percentage. Any help will be greatly appreciated! Hi, I was hoping...
  5. S

    Check my answers please.

    can somebody check my answers for me please. Classify the chemicals in the list in compounds, ions, elements or mixtures. Write the molecular formulas of compounds, ions and elements. Suggest components of the mixtures. 1. Deionised Water 2. Carbon 3. Bronze 4. Milk 5. Chlorine 6. Ammonia 7...
  6. S

    Final chem assignment due in on monday. Please check my answers

    Classify the chemicals in the list in compounds, ions, elements or mixtures. Write the molecular formulas of compounds, ions and elements. Suggest components of the mixtures. 1. Deionised Water 2. Carbon 3. Bronze 4. Milk 5. Chlorine 6. Ammonia 7. Sulphuric Acid 8. Sodium Nitrate 9. Bromine...
  7. S

    Can someone check my answers for me please?

    I would just like someone to check my answers for me. Im not sure my molar ratios are right. I'm going off of the info found here http://www.ehow.com/how_8149226_calculate-molar-ratio.html The only thing im missing is the molar ratio for Potassium + Iron (II) Sulphate. Any help on that is...
  8. T

    Can you please check these? (Stoichiometry problems)

    So i'm generally good with Molarity problems but on a few they threw mg/ml into the mix and its throwing me off. I think i did these right but could someone check them? The first problem is, you weigh out exactly 0.250g of CaCo3 (form. weight= 100.09g/mol) and disolve it in exaclty 250 ml of...
  9. R

    Just need someone to double check this chemistry question, Partition Coefficient?

    Partition coefficient Kp equation Kp= Csolvent1(gL-1) / Csolvent2(gL-1) How do you answer this question: The solubility in water of compound A is 10g/100ml. The solubility in ether for compound A is 1g/100ml. What is the partition coefficient (Kp ether/water) for compound A? I got a Kp= 0.1...
  10. L

    Double check my work solving for solubility?

    Is this the correct way to solve this problem? any feedback is greatly appreciated. The solubility of oxygen in water is 1.25 x 10^-3 M at 25 deg celsius and 1.0 atm. What will the solubility of oxygen be if the atmospheric pressure is 0.8 atm? I used Henry's Law to solve this. Solubility of...
  11. L

    Please check the answers for my practice sheet. I need to know whats wrong ASAP.

    If there are any wrong answers, please let me know which ones they are and what needs to be done to fix them. 1. The graph shows the change in concentration of one of the species in the reaction AB A + B + heat. If the graph indicates the reaction rate, then the concentration of which species...