Chem lab QuestionLab 1: Titration1/ Briefly define the following terms:

- Standard solution- Titration- Equivalence point- Indicator

2/ Why do you add phenolphthalein indicator solution to the vinegar solution prior to beginning the titration?3. A student performing this experiment titrates 22.32 mL of vinegar with 0.5172 M NaOH. The initial NaOH buret reading is 1.18 mL and the final NaOH buret reading is 21.35 mL. What is the molarity of HOAc in the vinegar sample?

Lab 2: Studying the Rate of Chemical Reaction1/ Briefly explain the meaning of the following terms as they pertain to this experiment.(a) reaction rate (b) rate equation (c) rate constant2/ The method of initial rates involves substituting the initial reactant concentrations into rate calculations. When you do the experiment, you will be given KMnO4 and H2C2O4 solutions of known concentrations. Will you use these known concentrations in your rate calculations? Briefly explain.3/ Consider the reaction of ammonium ions (NH4

+ ) and nitrite ions (NO2

-), shown in the following equation.NH4

+ (aq) + NO2- (aq) → N2 (g) + 2H2O (l)

Solutions containing NH4+ and NO2

- were mixed in various quantities and the following rate dala at a constant temperature were obtained:

Determination Initial concentration of NH4

+ mol/LConcentration of

NO2- mol/L

Initial rate for formation of N2

mol/L.s1 0.150 7.50 × 10-3 3.07 × 10-7

2 0.150 1.50 × 10-2 6.08 × 10-7

3 0.300 1.50 × 10-2 1.22 × 10-7

(a) Use the method of initial rates to find the order of the reaction with respect to NH4

+

(b) Use the method of initial rates to find the order of the reaction with respect to NO2

- (c) Calculate the rate constant, k, for the reaction of NH4+

and NO2-.

(d) Write the rate equation for the reaction of NH4+ and NO2

-.

Lab 3: Observing Signs of Chemical Reaction1/ How many types of transformations? Give example?2/ Briefly define three signs chemical changes? Give Example?Lab 4: Introducing Equilibrium1/ Briefly explain the meanings of the following terms as they related to this experimenta/ forward reactionb/ reverse reactionc/ chemical equilibriumd/ endothermic reaction2/ Which factors affecting with the chemical equilibrium? Give example?3/ Iron (III) ion Fe3+ reacts with thiocyanate ion (SCN-) to form a red complex ion with the formula [FeSCN]2+. The net ionic equation describing this reaction is given in the following equation:Fe3+ (aq, yellow) + SCN- (aq, colorless) ⇌ [FeSCN]2+ (aq, red)A student studying this equilibrium begins with an equilibrium mixture that is light pink. What change will the student observe when a solution containing Fe3+ ion is added to this mixture? Explain with Lechatelier’s principle.Lab 5: Oxidation – Reduction Reaction1/ Student placed a piece of aluminium (Al) in HCl solution. After some time, bubbles appeared in the solution and the Al became reduce in size. Write the equation describing this reaction that occurred?2/ A student found that reagent bottle containing FeSO4 solution had remained unstoppered overnight. The FeSO4 solution was pale yellow. Briefly explain what probably occurred?Lab 6: pH of acid, base, salt and buffer solution.1/ How many type of hydrolysis salt. Give example for each type and write hydrolysis equation.2/ Determine the pH of the following salts solutions: KCl, NaCN, Na2CO3, NH4Cl, Fe2(SO4)3 . 3/ How many types of buffer solution? Give example?