Basic analytical chemistry questions.

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#	Question
1	The solubility product , $K_{sp}$ is the equilibrium constant for the equilibrium established between a solid solute and its ions in a saturated solution. True OR False
2	Constant determinate errors become less significant with increased size of the sample. True OR False
3	The precise results are always accurate. True OR False
4	Consider the following equilibrium $HC_{2}O_{4}^{-}+HCO_{3}^{-} ightleftharpoons H_{2}CO_{3}+C_{2}O_{4}^{2-}$ Which of the following correctly identifies the order of Bronsted -Lowry acids and bases? $HC_{2}O_{4}^{-} ,HCO_{3}^{-}, H_{2}CO_{3},C_{2}O_{4}^{2-}$ base acid acid base acid base base acid acid base acid base base acid base acid Multiple choices
5	Which of the following is the weakest acid? $HK(K_{a}=6.8 imes 10^{-4})$ Acetic acid $(K_{a}=1.8 imes 10^{-5})$ $HNO_{2}(K_{a}=4.5 imes 10^{-4})$ $HClO(K_{a}=3.0 imes 10^{-8})$ $HCN(K_{a}=4.9 imes 10^{-10})$ Multiple choices
6	The $K_{a}$ of hypochlorous acid (HClO) is $3.0 imes 10^{-8}$ at 25°C. What is the % ionization of hypochlorous acid in a 0.015 M aqueous solution of HClO at 25°C? $1.4 imes 10^{-3}$ 14 $2.1 imes 10^{-5}$ $4.5 imes 10^{-8}$ 0.14 Multiple choices
7	The $K_{a}$ for formic acid $(HCHO_{2})$ is $1.8 imes 10^{-4}.$ What is the pH of a 0.35M aqueous solution of sodium formate $(NaCHO_{2})$ ? 5.36 8.64 10.71 4.20 3.29 Multiple choices
8	Four different CHE 101 students perform the calculation , 451.0g-15.46g and came up with answers given below. Which answer was the most acurate. 436g 435.54g 435g 435.5g Multiple choices
9	Which experimental technique reduces the systematic error in the investigation? Using a magnifying glass to enlarge the meniscus in a burette Repeating a titration a number of times and calculating an average titre. Using a larger amount of an indicator during a titration. Adjusting an electronic balance to remove its zero error before weighing a chemical. When comparing systematic errors and random uncertainties during an investigation, the following properties of errors in an experimental measurement may be considered : Error can possibly be removed Error cannot possibly be removed Error is of constant sign and size Error is of varying sign and size Error will be reduced by averaging repeated measurements Error will not be reduced by averaging repeated measurements Which properties apply to random uncertainties? I,II,III I,IV,VI II,IV,V II,III,V Multiple choices