Q1 An undergraduate weighed out 20grams of sodium
hydroxide pellets. If Na =23, O = 16 andH = 1, What is the mole of this
sodium hydroxide.
Q2 The base unit of a measured liquid called volume is _.
Q3 The base unit of a measured or weighed solid material in chemistry is _.
Q4 The technique of separation employed to purify an organic solid that may be contaminated by impurities is called _.
Q5 The technique employed for the separation of colours is called
Q6 The separation technique employed to separate mixtures of two or
more liquids with slightly different boiling points is called _.
Q7 The condensate collected during the vaporization of liquid is called
Q8 An apparatus that can be used to remove traces of water from a substance is _.
Q9 The process by which traces of water is removed by treating the liquid with suitable drying agents is called _.
Q10 The separation technique employed to purify an organic liquid or
to separate mixtures of liquids of different volatilities or boiling
points is called _.
Q11 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
Q12 The reagent that will not make any significant contribution to the theoretical yield is _.
Q13 A high percentage yield implies that _.
Q14 The reagent with a stoichiometric amount (in moles) that limits
the amount of desired product (in moles ) formed is called
Q15 The actual yield of product (in g or moles) expressed as a
percentage of the theoretical yield (in g or moles ) is called _.
Q16 The number of protons or electrons in the atom of an element is equal to the of the element.
Q17 Calculate the [OH^{-}] of an aqueous solution of Ph=11
Q18 An acid HA has a pka of 4.5, what is the Ka value?
Q19 An acid HA has a pka of 4.5. What is the concentration of $$H_{3}^{+} $$ in 0.110M solution of the acid ?
Q20 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?
Q21 When two or more elements combine chemically in fixed proportion by mass, is formed
Q22 A mixture in which the components are evenly distributed and the
composition is uniform throughout the mixture is called mixture.
Q23 Dissolution 0f sodium chloride in water results in type of mixture
Q24 The types of mixtures are _, _--- mixture.
Q25 Convert 2 moles of NaOH to grams of NaOH. Answer is _.
Q26 The molar mass of $$Na_{2}CO_{3}$$
Q27 When propane reacts with oxygen, the products are and
Q28 Convert 500g of $$ Na_{2}CO_{3}$$ to moles
Q29 A compound in grams is converted to moles by diving by _.
Q30 The smallest unitof a compound that manifest all the chemical properties of the compound is called _.
Q31 A mixture in which the components are not evenly distributed and the composition is not uniform is called mixture.
Q32 Mixtures with particle sizes between 2 to 1000 nanometre are called _.
Q33 The label on a stock bottle of acid reads : 56% by mass and 1.25
specific gravity. If the molar mass of the acid is 56, what is the the
concentration in grams per dm_{3}
Q34 Mixtures with particle sizes greater than 1000 nanometres are called _.
Q35 Mixture made up of sand and iron filing is a type of mixture
Q36 The formula for sodium carbonate is _.
Q37 The formula for caustic soda is _.
Q38 In balancing this equation $$Na_{2}CO_{3}—› ? NaOH + CaCO_{3}$$ . ? is _.
Q39 In a solution , the component in smaller amount is called _.
Q40 In a solution, the component in larger amount is called .
Q41 A substance that is made up of two or more substances which are not chemically combined is called _.
Q42 Calculate the percentage by mass of Hydrogen in $$NH_{3}$$
Q43 Calculate the percentage by mass of Nitrogen in $$NH_{3}$$
Q44 0.0055 has significant figure(s)
Q45 The amount of product obtained from an experiment is called _.
Q46 The amount of product expected from given amounts of starting materials is called _.
Q47 In a chemical reaction, the balanced chemical equation which shows
the quantitative relationship between masses of reactants and products
is known as _.
Q48 The amount of energy required to break a particular bond is called _.
Q49 12.25mL has significant figure(s)
Q50 Calculate the percentage by mass of Oxygen in $$CH_{3}OH$$
Q51 Calculate the percentage by mass of Hydrogen in $$CH_{3}OH$$
Q52 Calculate the percentage by mass of carbonIin $$CH_{3}OH$$
Q53 An organic compound was found by analysis to contain 42.90%
carbon, 2.40% Hydrogen , 16.70% Nitrogen and 38.0% of oxygen.
Calculateits empirical formular. (Relative atomic masses : C=12.00,
H=1.008, N=14.00, O=16.00).
Q54 6.02Χ10^{23} is called _.
Q55 A chemical formula which shows the actual numbers and types of atoms present in one molecule of a compound is called _.
Q56 A chemical formular which represents the elemental composition of a
formula unit of the compound in terms of smallest whole number ratios
of the atoms present is called _.
Q57 The number of atoms in the atomic mass of every element is called _.
Q58 The unit of mole is _.
Q59 Calculate the formular mass of potassium carbonate.(Relative atomic masses : K=39.10amu, C=12.01amu, 16.00amu).
Q60 The empirical formula obtained for a compound is $$
C_{3}H_{2}NO_{2}$$. The gram molecular mass of the compound is found to
be 168g. Determine its molecular formular. (Relative atomic masses :
C=12.00, H=1.008, N=14.00, O=16.00).
Q61 A substance with a pH value of >7 < 10 is a --------------.
Q62 If actual yield of an ester is 32.7g and theoretical yield is 35.1g .What is the percentage yield of the ester?
Q63 The formular obtained by multiplying the number of each atom in the empirical formular by n is called ------------
Q64 There are _______ types of titrimetric analysis.
Q65 In titration, the experimentally determined stoichiometric point of the titration is referred to as--------------.
Q66 In a standardization titration involving
hydrochloric acid and sodium carbonate, a student recorded the following
results for the volume of hydrochloric acid used against 10.00mL of the
sodium carbonate solution : 15.60; 14.50; 14.70 aqnd 14.20. If the
concentration of the $$Na_{2}CO_{3}$$ standard solution is 0.75moldm^-3,
calculate the concentration of the HCl solution
Q67 The number of gram-equivalent weight of solute in one cubic decimeter of solution is __________.
Q68 There are _____ different techniques for determination of an unknown sample in titrimetric analysis.
Q69 The solution whose concentration is known is called ______.
Q70 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
________.
Q71 The procedure by which a solution of known
concentration iss Added to another solution until the chemical reaction
between the two ssolutes is complete is ______.
Q72 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?
Q73 $$The label on a stock bottle of an acid reads:
56% by mass and 1.25 specific gravity. If the molar mass of the acid is
56, find the volume of this acid that is required to prepare 250cm^{3}
of 1.0 molar concentration of the acid$$.
Q74 3.47g sodium carbonate was dissolved in a
250millilitre standard flask. What is the concentration of the resulting
solution
Q75 $$The label on a stock bottle of an acid reads:
56% by mass and 1.25 specific gravity. If the molar mass of the acid is
56, find the moles per dm^{3}$$
Q76 The residue of a chemical reaction is allowed to cool in a ________.
Q77 In this equation $$2NaHCO_{3} → Na_{2}CO_{3} + ? + CO_{3}$$, the compound represented by ? is _________ .
Q78 When a substance is not available in a pure form, its solution can be standardized by ---------------.
Q79 A standard solution is a ----------------.
Q80 A standard solution of a substance can be prepared if the substance can be obtained in ______ state.
Q81 What is the oxidation state of chromium in potassium dichromate?
Q82 $$The label on a stock bottle of an acid reads:
56% by mass and 1.25 specific gravity. If the molar mass of the acid is
56, find the concentrationin grams per dm{3}$$.
Q83 A solution of which the concentration is accurately known is __________.
Q84 $$Weight of solute in gram per volume of solutions in cm^{3}$$ multiplied by 100 is________.
Q85 Moles of solute per volume of ssolution in one cubic decimeter is _______.
Q86 If $$15cm^{3 }$$ of 10.25M HCl solution is made
up to volume in a 500mL volumetric flask, what will be its new
concentrion?
Q87 The pH scale range is ________.
Q88 The product represented by the ? in the equation $$CH_{3}COO^{-}+ H^{+} + Na^{+} +OH^{-}→ ?+ H_{2}O$$ is ______.
Q89 The reactant represented by the ? In the equation $$H_{2}O^{+}$$ +$$ ?$$ → $$2H_{2}O$$ is ______.
Q90 In a typical expeiment in a laboratory, 4.50g of
sulphuric acid in $$250cm^{3}$$ of water was titrated with an impure
solution of 5.24g of sodium hydroxide contained in $$1dm_{3} $$ . If the
titre values of the experiment were $$20.50$$, $$22.45$$, $$22.60$$ and
$$22.50cm^{3}$$ respectively. Determine the amount in moles of the
acid.
Q91 The oxidation state of cromium in $$Cr_{2}O_{7}^{2-}$$ is ________.
Q92 The heat of reaction is measured by the use of __________.
Q93 What is the oxidation state of iodine in iodate ion?
Q94 If the mass of an impure acid is 18.0g and mass of impurity is 12.3g, calculate the percentage impurity of the solution.
Q95 The titrimetric analysis involving the titration
of EDTA, an organic ligand with a calcium solution cxould be classified
as ------------- titration.
Q96 The titration involving potassium permanganate
,$$KMnO_{4}$$ and ferrous sulphate $$FeSO_{4}$$ is an example of a
----------------- titration.
Q97 All thesse are examples of exothermic reactionss EXCEPT ______.
Q98 A suitable indicator for titration between weak acid and strong base is _________.
Q99 A substance that loses an electron is said to be _______.
Q100 The reaction between aqueous sodium hydroxide and aqueous hydrochloric acid is a _______ reaction
Q101 The pH of a solution is a measure of ------------- conentration of the solution.
Q102 If a reaction is carried out at a constant
pressure, the absolute value of the heat of reaction is equal to the
absolute value of the ___________ of the reaction
Q103 A process that is accompanied by a heat gain is said to be __________.
Q104 The titration of a strong acid against a weak base is suitably carried out using ------------
Q105 The oxidation state of C in $$H_{2}C_{2}O_{4}$$ is ___________.
Q106 Calculate the number of mole contained in a
solution of tetraoxosulphate VI acid, if the titre value on titration
against $$20cm^{3}$$ 0.5 M sodium carbonate is $$20.24cm^{3}$$.
Q107 The sum of the oxidation states of all elements in a neutral compound add to _______.
Q108 A metal X that raects with metal Y in a solution
of Y but does not react with Z in a solution of Z means that
--------------.
Q109 The SI designation candela is for --------------base unit.
Q110 The pH of a solution is a measure of the ______.
Q111 The first aid given to a person that ingested
poisonous chemical in the laboratory include all these EXCEPT
----------------.
Q112 The second action to perform to resucitate a victim of gas inhaltion in the laboratory is to ----------------.
Q113 Towards the _______ point, both coloured forms will be present in appreciable quantities.
Q114 A measure of the hydrogen ion concentration in a solution is _________.
Q115 An indicator that is colourless in acidic solution is ______.
Q116 When an alkalis chemical splashes into the eye, the second action to be carried out is ---------------.
Q117 Acid base titration involves a __________ reaction
Q118 When an acidic chemical splashes into the eyes, the first thing to do is ---------
Q119 Do not use flat-bottomed flasks in in vacuum experiment is a ------------- hazard
Q120 All these are safety precautions in a chemistry laboratory EXCEPT -----------.