1. N

    How do I calculate the concentration of a stock solution?

    How do I calculate the concentration of a stock solution prepared in a 100cm3 volumetric flask that contains 75mg of Acesulfame K, 50mg of Saccharin and 200mg of Aspartame ?
  2. M

    calculate alkalinity hardness of water

    the first part is ok help as from hydrogen ions
  3. J

    Calculate ppm of CO2 in seawater from flow rate?

    This is likely a simple calculation but I'm not sure exactly how to do it. I'm injecting pure CO2 at at a rate of 35 ml/min into seawater which has a flow rate of 6000 ml/min and want to calculate a predicted dissolved CO2 in seawater in ppm. Anyone know how to do this off hand?
  4. L

    Calculate reaction orders.

    Hi I am new here and really hoping someone can help me with this question I have please...… (B) Through experimentation, you note that at high temperatures ethyl chloride produces HCl and ethylene by the following reaction: CH3CH2Cl(g) → HCl(g) + C2H4(g) Using the rate data for the...
  5. G

    How to calculate final temperature question.

    Hi, I am new to this forum. I am not pretty sure about the answer i got so i came to here in order to get help. Iceman, a member of the Marvel superhero team known as the X-men,enters a friendly duel with the Human Torch (Fantastic Four), and gets hit by a fireball worth 562kJ. Ice man is...
  6. J

    How to calculate amount by weight, of a powder in a liquid

    I need to add .2% of a flavor powder to an amount of milk. How would I calculate the amount, in grams, of the flavor powder that would be required to go into 8oz of milk. Thank you.
  7. C

    How to calculate molarity of a dilute solution?

    An unknown solution has a molarity of 1.30 x 10^-5 M. 3.0 mL of the solution is placed in a test tube with 2.0 mL of water. Then 1.0 mL of bleach with a molarity of 0.712 M is added. How do you calculate the molarity of this dilute solution?
  8. S

    Calculate volume of H2O2

    A student needs to prepare 50.0 mL of 1.00 M aqueous H2O2 solution. Calculate the volume of 5.1 M H2O2 stock solution that should be used.
  9. C

    Calculate moles

    Question: Nitric acid is extensively used in the manufacturing of fertilizer. A bottle containing 75mL of nitric acid solution is labelled 6.0M nitric acid. How many moles of nitric acid is in the bottle? My answer: M=moles of solute / moles of solution thus moles of solute = M x moles of...
  10. J

    How would I calculate the Yield. Please Help

    4.00 g of carbon reacts with 4.00 g of oxygen gas as shown in the balanced chemical equation below. Calculate the yield for the reaction if 3.99 g of CO2 (44.0 g/mol) is isolated from the reaction. C(s) + O2(g) → CO2(g) I know the answer is 72.5% but how do you get to that answer.
  11. U

    Calculate the concentration?

    The rate constant for the reaction 2N2O5(g) → 4NO2(g) + O2(g) is equal to 4.37 x 10–5 s–1 at 30 ºC. If the initial concentration of N2O5 is 0.372 M what concentration of NO2 will be observed after 145 minutes? Assume that initially no NO2 was present in the reaction vessel. Thanks in advance
  12. A

    Calculate pH of a solution given the mass and the acid dissociation constant

    Hi everyone! The problem: "2,50 g of ammonium chloride NH4Cl is dissolved in water and the volume of the solution is 100 cm^3. At current temperature, the Ka for NH4^+ is 5,7 * 10^-10 mol/dm^3 What pH does the solution of ammonium chloride have?" My attempt: H2O + NH4^+ <=> H3O^+ + NH3...
  13. A

    Calculate the label concentration of the NaOH solution

    I've been stuck on this question for hours now, I dont really know where to start and I was wondering if you guys could help me out The concentration of a solution of NaOH of unknown concentration was determined in the following titration: 25.00-mL aliquots of the NaOH solution, measured by...
  14. N

    How to calculate amount of Fe in a vitamin tablet

    Using the equation from the standards I obtained I calculated the concentration of the unknown to be C =1.941x10^-6 mol/L. DF=100 Vtotal = 100mL MWFe = 55.845g/mol mass of sample = 1.4375g 1.941x10^-6mol/L x100 = 1.941x10^-4 mol/L x 0.1L = 1.941x10^-5 mol x 55.8452g = 1.08mg This is...
  15. L

    Some chemistry questions I need help with

    1. a)You put [H2] = 0,70M, [I2] = 0,70M and [HI] =1,50M. And the K value is 49. Decide the equilibrium concentrations. H2 + I2 <-> 2HI b) Which concentration HI gets inserted if the iodine concentration at a new equilibrium is 0,42Molar. The K value is still 49. c) What happens with the...
  16. H

    Calculate the volumes of solution III required to make up the standard solutions?

    I.60 mL of Fe(NO3)3 (0.20 M in 0.50M HNO3) for standard solutions II. 70 mL of Fe(NO3)3 (2.0 x 10^-3 M in 0.50 M HNO3) for unknown solutions III. 60 mL of KSCN (2.0 x 10^-3 M in 0.50 M HNO3) for both standard and unknown solutions IV. 100 mL of HNO3 (0.50 M) as solvent Find the volume of...
  17. A

    Calculate the Mass Fractions of Gold and Copper

    A 9.40g wedding band is made up of gold and copper, and has a 4.382x10^22 atoms. Calculate the mass fractions of gold and copper in this 18-carat gold alloy. I have gotten this far: 1) (Au) = gold = x (Cu) = copper = y 9.40g = x + y 2) Ntotal = 4.382x10^22...
  18. D

    Calculate ΔH° problem

    I have a final exam in a couple of days so any help would be much appreciated. These kind of problems are usually easy but I'm just not able to get the right answer for this one. The problem is in the link here (see question 13) ...
  19. C

    Calculate volume of HCl needed to change buffer pH by 1 unit???

    How do you calculate the amount of HCl needed to change the pH of a NH3/NH4+ buffer by 1 unit? There was 100mL of NH3 2M and 10.698g of NH4 0.5M and then this was mixed with 400mL of water to make 500mL buffer solution. Only 80mL of this was used for each trial. HCl was 1M. Starting pH was...
  20. J

    Formulas to calculate problems

    Can someone tell me the formulas to calculate these problems I have for my chemistry class? I can'y find a formula that uses just the given information to do the problems. Here they are: 1 Considering the reaction: 2KClO3 → 2KCl + 3O2 How...