Category: CHM191 0 CHM191 1 / 50 If actual yield of an ester is 32.7g and theoretical yield is 35.1g .What is the percentage yield of the ester? 0.932 0.0932 0.009 0.0093 2 / 50 When two or more elements combine chemically in fixed proportion by mass, _________ is formed Check 3 / 50 Convert 500g of $$ Na_{2}CO_{3}$$ to moles _______ Check 4 / 50 There are _____ different techniques for determination of an unknown sample in titrimetric analysis. 3 4 2 5 5 / 50 The smallest unit of a compound that manifest all the chemical properties of the compound is called ________ Check 6 / 50 The residue of a chemical reaction is allowed to cool in a ________ oven fume cupboard dessicator furnace 7 / 50 When two or more elements combine chemically in fixed proportion by mass, is formed _________ Check 8 / 50 $$The label on a stock bottle of an acid reads: 56% by mass and 1.25 specific gravity. If the molar mass of the acid is 56, find the volume of this acid that is required to prepare 250cm^{3} of 1.0 molar concentration of the acid$$. $$3.0cm^{3}$$ $$4.0cm^{3}$$ $$5.0cm^{3}$$ $$2.0cm^{3}$$ 9 / 50 The number of protons or electrons in the atom of an element is equal to the _________ of the element Check 10 / 50 The formular obtained by multiplying the number of each atom in the empirical formular by n is called ____________ None of the above Structural formula Molecular formula Chemical formula 11 / 50 The types of mixtures are _________, _________ mixture. Check 12 / 50 The actual yield of product (in g or moles) expressed as a percentage of the theoretical yield (in g or moles ) is called ____________ Check 13 / 50 The procedure by which a solution of known concentration is Added to another solution until the chemical reaction between the two ssolutes is complete is ______. qualitative analysis Gravimetric analysis volumetric analysis Titrimetric analysis 14 / 50 In titration, the experimentally determined stoichiometric point of the titration is referred to as _______ stop point Critical point Equivalence point Flash point 15 / 50 The solution whose concentration is known is called ___________ titre value saturated solution supersaturated solution titrant 16 / 50 Calculate the $$[H^{+}] $$of an aqueous solution wity $$[OH^{-}] of 1× 10^{-10}M$$. What is the pH of the solution? Is the solution acidic or basic? ________ Check 17 / 50 3.47g sodium carbonate was dissolved in a 250millilitre standard flask. What is the concentration of the resulting solution 0.66M 0.40M 0.52M 0.13M 18 / 50 An acid HA has a pka of 4.5. What is the concentration of $$H_{3}^{+} $$ in 0.110M solution of the acid ? ________ Check 19 / 50 $$The label on a stock bottle of an acid reads: 56% by mass and 1.25 specific gravity. If the molar mass of the acid is 56, find the moles per dm^{3}$$ $$25.5moldm^{3}$$ $$35.5moldm^{3}$$ $$12.5moldm^{3}$$ $$45.5moldm^{3}$$ 20 / 50 A compound in grams is converted to moles by diving by ________ Check 21 / 50 An acid HA has a pka of 4.5, what is the Ka value? _________ Check 22 / 50 The process by which traces of water is removed by treating the liquid with suitable drying agents is called _________ Check 23 / 50 An apparatus that can be used to remove traces of water from a substance is ________ Check 24 / 50 In this equation $$2NaHCO_{3} → Na_{2}CO_{3} + ? + CO_{3}$$, the compound represented by ? is __________ $$NO_{3}$$ NO $$NO_{2}$$ $$N_{2}O$$ 25 / 50 The technique of separation employed to purify an organic solid that may be contaminated by impurities is called __________ Check 26 / 50 A separation technique that is used to isolate a desired solid from a solid -liquid mixture or for freeing a desired liquid of solid impurities is called _________ Check 27 / 50 The separation technique employed to purify an organic liquid or to separate mixtures of liquids of different volatilities or boiling points is called __________ Check 28 / 50 There are _______ types of titrimetric analysis. 5 3 4 2 29 / 50 The reagent with a ________ stoichiometric amount (in moles) that limits the amount of desired product (in moles ) formed is called Check 30 / 50 A standard solution of a substance can be prepared if the substance can be obtained in ______ state. neutral state acidic state pure state impure state 31 / 50 The technique employed for the separation of colours is called _________ Check 32 / 50 When a substance is not available in a pure form, its solution can be standardized by ___________ Titrating againt a substance of unknown concentration Re- crystallizing the substance and diluting it Preparing a new solution of the substance Titrating against a substance of known concentration 33 / 50 The base unit of a measured liquid called volume is __________ Check 34 / 50 A high percentage yield implies that ___________ Check 35 / 50 The number of gramequivalent weight of solute in one cubic decimeter of solution is ______ Molarity Normality Norlality Molality 36 / 50 Calculate the [OH^{-}] of an aqueous solution of Ph=11 ____________ Check 37 / 50 A mixture in which the components are evenly distributed and the composition is uniform throughout the mixture is called _________ mixture. Check 38 / 50 The separation technique employed to separate mixtures of two or more liquids with slightly different boiling points is called __________ Check 39 / 50 A standard solution is a _________ Dilute solution Measured solution Concentrated solution Solution of known concentration 40 / 50 When propane reacts with oxygen, the products are ______ and ________ Check 41 / 50 The concentration of the pure HCl used is 11.7 molar. If $$20.0cm^{3}$$ V1 of 1 1.7 molar of $$C_{1}$$ of HCl is diluted to 250cm^{3} of V_{2}, then the new concentration C_{2} will be ______ $$0.718moles dm^{-3}$$ $$9.36moles dm^{-3}$$ $$0.825 moles dm^{-3}$$ $$0.936moles dm^{-3}$$ 42 / 50 An undergraduate weighed out 20grams of sodium hydroxide pellets. If Na =23, O = 16 andH = 1, What is the mole of this sodium hydroxide. ___________ Check 43 / 50 The molar mass of $$Na_{2}CO_{3}$$ ________ Check 44 / 50 A substance with a pH value of >7< 10 is a ______________ Weak base Weak acid Strong acid Strong base 45 / 50 The condensate collected during the vaporization of liquid is called _________ Check 46 / 50 Convert 2 moles of NaOH to grams of NaOH. Answer is ________ Check 47 / 50 Dissolution 0f sodium chloride in water results in __________ type of mixture Check 48 / 50 The reagent that will not make any significant contribution to the theoretical yield is _________ Check 49 / 50 The base unit of a measured or weighed solid material in chemistry is ________ Check 50 / 50 From the equation $$2HCl + Na_{2}CO_{3} → 2NaCl + CO_{2} + H_{2}O$$, given that 2 moles of HCl reacted with 1 mole of $$Na_{2}CO_{3}$$. What was the concentration of the acid? $$0.103moldm^{-3}$$ $$10.3moldm^{-3}$$ $$103moldm^{-3}$$ $$1.03moldm^{-3}$$ Restart quiz Rate this quiz Send feedback
