One of the most valuable properties of water is its ability to dissolve. An individual water molecule has a bent shape with a H-O-H bond angle of approximately 105 degrees. Water is polar thus having positive & negative partial charges on its ends. Water: The Universal Solvent.
One of the most valuable properties of water is its ability to dissolve.
An individual water molecule has a bent shape with a H-O-H bond angle of approximately 105 degrees.
Water is polar thus having positive & negative partial charges on its ends.
& move around
M = moles solute
volume (L) solution
[Co2+] = 1 x 0.50M = 0.50M
[NO3-] = 2 x 0.50M = 1.0M
[Fe3+] = 2.0M
[ClO4-] = 6.0M
(step 1) ZnCl2(s) Zn2+(aq) + 2Cl-(aq)
(step 2) [Cl-] = 2 x 1.0 x 10-3 = 2.0 x 10-3M
(step 3) 1.75 L x 2.0 x 10-3 mole Cl- =
3.5 x 10-3 moles of chloride ions
M1V1 = M2V2 or McVc = MdVd
15.2 g PbSO4
A, Strong acids and bases are strong electrolytes, as indicated by the brightly lit bulb. B, Weak acids and bases are weak electrolytes.
Because both ionize completely, the H+ ions and OH- ions react with each other to form water molecules.
Basic: HNO3(aq) + NaOH (aq)
Ionic: H+ (aq) + NO3-(aq) + Na+ (aq) + OH-(aq)
Net Ionic: H+ (aq) + OH-(aq) H2O (l)
A two-step process occurs:
HB (aq) H+ (aq) + B- (aq)
H+ (aq) + OH- (aq) H2O (l)
Net Ionic:HX + OH- X- + H2O
This is also a two-step process:
NH3 + H2O NH4+ + OH-
H+ + OH- H2O
8.75 x 10-2 L
0.024 moles H2O, [H+] = 0, [OH-] = 0.123 M
You perform an acid-base titration to standardize an HCl solution by placing 50.00 mL of HCl in a flask with a few drops of indicator solution. You put 0.1524 M NaOH into the buret, and the initial reading is 0.55 mL. At the end point, the buret reading is 33.87 mL. What is the concentration of the HCl solution?
In a titration, it is found that 25.0 mL of 0.500 M NaOH is required to react with
H2A(aq) + 2OH-(aq) 2H2O + A2-(aq)?
HC9H7O4 (s) + OH- (aq) H2O + C9H7O4 - (aq)
Split in 2 half reactions.
Net ionic equation:
Zn (s) + 2H+ (aq) H2 (g) + Zn+2 (aq)
(A) 2.0 M(B) 2.4 M(C) 4.0 M(D) 4.5 M (E) 7.0 M
(A) 42.8 grams of KIO3 and add 2.00 kilograms of H2O(B) 42.8 grams of KIO3 and add H2O until the final homogeneous solution has a volume of 2.00 liters(C) 21.4 grams of KIO3 and add H2O until the final homogeneous solution has a volume of 2.00 liters(D) 42.8 grams of KIO3 and add 2.00 liters of H2O(E) 21.4 grams fo KIO3 and add 2.00 liters of H2O
(A) 0.150 M(B) 0.160 M(C) 0.200 M(D) 0.240 M(E) 0.267 M
(A) 3.10 grams(B) 12.0 grams(C) 29.4 grams(D) 294 grams(E) 300. grams
I. The density of waterII. The density of the solutionIII. The molar mass of sucrose
(A) I only(B) II only(C) III only(D) I and III(E) II and III
A) Pb2+ (aq)B) Zn2+(aq)C) CrO42¯ (aq)D) SO42¯ (aq)E) OH¯ (aq)
A) [PO43¯] < [NO3¯] < [Na+]B) [PO43¯] < [Na+] < [NO3¯]C) [NO3¯] < [PO43¯] < [Na+]D) [Na+] < [NO3¯] < [PO43¯]E) [Na+] < [PO43¯] < [NO3¯]
A) 50.0 mLB) 60.0 mLC) 100. mLD) 110. mLE) 120. mL
(A) Ag2CO3 + 2H+ + 2 Cl¯ ---> 2 AgCl + H2O + CO2
(B) 2Ag+ + CO32¯ + 2 H+ + 2 Cl¯ ---> 2 AgCl + H2O + CO2(C) CO32¯ + 2 H+ ---> H2O + CO2(D) Ag+ + Cl¯ ---> AgCl(E) Ag2CO3 + 2H+ ---> 2Ag+ + H2CO3
5 Fe2+ + MnO4¯ + 8 H+ <===> 5 Fe3+ + Mn2+ + 4H2O
(A) 0.0010 M(B) 0.0056 M(C) 0.028 M(D) 0.090 M(E) 0.14 M
(a)Write the balanced equation for the titration reaction, shown unbalanced below:
MnO4- + H2C2O4 + H+ Mn2+ + CO2 + H2O
(i) Indicate which substance is the oxidizing agent and which substance is the reducing agent.
(b)The titration of the H2C2O4 obtained required 35.62 milliliters of 0.1092 molar MnO4- solution. Calculate the number of moles of H2C2O4 that reacted with the MnO4-
(c)Calculate the number of moles of CaCO3 in the original sample.
(d)Calculate the percentage by weight of CaCO3 in the original sample.
Pb(NO3)2(s) + 2 NaI(aq) PbI2(s) + 2NaNO3(aq)
(a)List an appropriate observation that provides evidence of a chemical reaction between the two compounds.
(b)Calculate the number of moles of each reactant.
(c)Identify the limiting reactant. Show calculations to support your identification.
(d)Calculate the molar concentration of NO3–(aq) in the mixture after the reaction is complete.
(a)The amount of acetylsalicylic acid in a single aspirin tablet is 325 mg, yet the tablet has a mass of 2.00 g. Calculate the mass percent of acetylsalicylic acid in the tablet.
(b)A student dissolved 1.625 g of pure acetylsalicylic acid in distilled water and titrated the resulting solution to the equivalence point using 88.43 mL of 0.102 M NaOH(aq). Assuming that acetylsalicylic acid has only one ionizable hydrogen, calculate the molar mass of the acid.
5 Fe2+(aq) + MnO4–(aq) + 8 H+(aq) 5 Fe3+(aq) + Mn2+(aq) + 4H2O(l)
(a)What is the oxidation number of manganese in the permanganate ion, MnO4–(aq)?
(b)Identify the reducing agent in the reaction represented above. Explain your reasoning.
(c)Describe the color change that occurs in the flask when the end point of the titration has been reached. Explain why the color of the solution changes at the end point.
(d)Let the variables g, M, and V be defined as follows:
g = the mass, in grams, of the sample of the iron(II) compound
M = the molarity of the MnO4–(aq) used as the titrant
V = the volume, in liters, of MnO4–(aq) added to reach the end point
(i)The number of moles of iron in the sample
(ii)The mass of iron in the sample, in grams
(iii)The mass percent of iron in the compound
(e)What effect will adding too much titrant have on the experimentally determined value of the mass percent of iron in the compound? Justify your answer.
(a)A sample of solid iron(III) oxide is reduced completely with solid carbon.
(ii)What is the oxidation number of carbon before the reaction, and what is the oxidation number of carbon after the reaction is complete
(b)Equal volumes of equimolar solutions of ammonia and hydrochloric acid are combined.
(ii)Indicate whether the resulting solution is acidic, basic, or neutral. Explain.
(c)Solid mercury(II) oxide decomposes as it is heated in an open test tube in a fume hood.
(ii)After the reaction is complete, is the mass of the material in the test tube greater than, less than, or equal to the mass of the original sample? Explain.
(a) A small piece of sodium is placed in a beaker of distilled water.
(ii)The reaction is exothermic, and sometimes small flames are observed as the sodium reacts with the water. Identify the product of the reaction that burns to produce the flames
(b)Hydrogen chloride gas is oxidized by oxygen gas.
(ii)If three moles of hydrogen chloride gas and three moles of oxygen gas react as completely as possible, which reactant, if any, is present in excess? Justify your answer.
(c)Solid potassium oxide is added to water.
(ii)If a few drops of phenolphthalein are added to the resulting solution, what would be observed? Explain.