Other Chemistry Answers

Does asphalt parking contribute to photochemical smog

1. What is the mass percent (m/m) of KCl solution made by dissolving 5.0 g of KCl in 65 g of H2O?
2. What is the volume percent (v/v) of Br2 in a solution prepared by dissolving 10 mL of bromine (Br2) in the solvent carbon tetrachloride to make 0.2 L of solution?
3. What is the mass/volume percent (m/v) of KOH in a solution prepared by dissolving 0.02 Kg of KOH in enough water to make 250 mL of solution?
4. Calculate the mass percent (m/m) for 12 g of sugar in 0.225 Kg of tea solution with sugar?
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5. A saline solution with a mass of 355 g has 0.0365 Kg of NaCl dissolved in it. What is the mass/mass percent concentration of the solution?
6. What is the amount (in g) of hydrogen peroxide (H2O2) needed to make a 3.0 kg , 2.0 % (mass/mass) H2O2 solution?

1. A solution of NaCl is neutral, with an expected PH of 7. If electrolysis was carried out on 500 mL of an NaCl solution with a current of 0.500 A, how many seconds would it take for the PH of the solution to rise to a value of 9? (PH is related to H+ concentration by PH = -log [H+]).

2.42.10cm3 of a solution containing 2g of an acid (H2X) per dm3 neutralizes 28cm3 of solution containing 2.5g of potassium hydroxide per dm3. Calculate
i.The concentration of the acid in moles/dm3
ii.The molar mass of the acid H2X
iii.The value of X
iv.The percentage by mass of X

Describe the ways of classifying amino acids and give example of each class

calculate the amount in moles of H2SO4 present in 25.0cm3 of 1.00moldm-3 H2SO4

5. STOICHIOMETRY QUESTION: Silver is widely used for jewelry and for tableware. The tarnish on silver is a layer of silver sulfide that forms according to the following reaction:

4Ag + 2H2S + O2 → 2Ag2S + 2H2O

What mass of silver sulfide would form from the reaction of 0.015 g of silver?

49. When the following oxidation-reduction equation representing a reaction that takes place in acidic solution is correctly balanced using the smallest possible whole number coefficients. the coefficients before HSO3^-, MnO4 and the H2O are: HSO3^- + MnO4^- = Mn^2+ + SO4^2- 50. In the oxidation-reduction reaction below: ClO3 + Cl = Cl2 + ClO2 a) O is oxidized and Cl is reduced. b) Cl is oxidized and O is reduced. c) Cl is both oxidized and reduced. d) O is both oxidized and reduced. e) None of the above is true.

42 ml of 1.1 mol/L hydrochloric acid reacted with excess sodium hydroxide. How many moles of sodium chloride were produced?

10.00grams of magnesium acetate is dissolved in 100.00 ml of DI water . The molar mass is 142.41g/mol . Calculate the molarity