Which of the following statements is TRUE?

The frequency of radiation increases as the wavelength decreases.

Ultraviolet light has longer wavelength than visible light.

The energy of radiation decreases as the wavelength decreases.

Wave number of an electromagnetic radiation increases as wavelength increases.

Grade 12 Chemistry national exam, 2005 E.C. (2013 G.C.)

74 questions · 120 minutes. The first 5 answers are shown with explanations; sit the whole paper timed in the app to get your score and the textbook page behind every question.

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1.Which of the following is NOT a basic SI unit?
- A. Candela
- B. Gram
- C. Mole
- D. Second
Answer: B. The key idea is that SI has seven basic units, including the kilogram, not the gram. B is correct because the basic SI unit of mass is the kilogram. A, C, and D are basic SI units: the candela, mole, and second. Textbook: Grade 9, unit 2 · section 2.1.
2.Which of the following statements is TRUE?
- A. Ultraviolet light has longer wavelength than visible light.
- B. The energy of radiation decreases as the wavelength decreases.
- C. The frequency of radiation increases as the wavelength decreases.
- D. Wave number of an electromagnetic radiation increases as wavelength increases.
Answer: C. For electromagnetic waves, frequency increases when wavelength decreases. Since $c=\lambda\nu$, a shorter wavelength means a higher frequency, so C is true. Ultraviolet has a shorter wavelength than visible light; energy increases, not decreases, as wavelength decreases; and wave number $\tilde{\nu}=1/\lambda$ decreases as wavelength increases, so A, B, and D are false. Textbook: Grade 11, unit 1 · section 1.5.1.
3.Which of the following ionic compounds is formed from the reaction between magnesium and nitrogen?
- A. $\mathrm{MgN_2}$
- B. $\mathrm{Mg_2N_2}$
- C. $\mathrm{Mg_3N_2}$
- D. $\mathrm{Mg_2N_3}$
Answer: C. The question tests how ion charges determine an ionic compound’s formula. Magnesium forms $\mathrm{Mg^{2+}}$ and nitrogen forms $\mathrm{N^{3-}}$, so balancing the charges gives $\mathrm{Mg_3N_2}$. A is wrong because its formula does not balance the charges. B is wrong because its formula reduces to a ratio that does not balance the charges. D is wrong because its formula also leaves the total charges unbalanced. Textbook: Grade 9, unit 5 · section 5.2.
4.Which of the following molecules represents a non-polar covalent bond?
- A. B-Cl
- B. C-Cl
- C. Cl-Cl
- D. Mg-Cl
Answer: C. A non-polar covalent bond shares electrons equally between its atoms. In $\mathrm{Cl-Cl}$, both atoms are the same, so they attract the shared electrons equally. A is wrong because $\mathrm{B-Cl}$ is polar. B is wrong because $\mathrm{C-Cl}$ is polar. D is wrong because $\mathrm{Mg-Cl}$ is mainly ionic, with electrons transferred rather than shared equally. Textbook: Grade 9, unit 5 · section 5.3.
5.Which of the following groups in the periodic table has paramagnetic atoms?
- A. Group zero
- B. Group IIA
- C. Group IIB
- D. Group IVA
Answer: D. Paramagnetic atoms have one or more unpaired electrons. Atoms in group IVA have two unpaired electrons in their outer $p$ orbitals, so they are paramagnetic. Group zero atoms and group IIA and IIB atoms have paired electrons, so A, B, and C are not correct. Textbook: Grade 11, unit 1 · section 1.7.1.
6.How many types of cubic unit cells are known?
- A. 2
- B. 3
- C. 4
- D. 5
Answer, explanation and textbook page: open in the app.
7.What is the process that converts liquid vegetable oils to solid fats?
- A. Hydration
- B. Hydrogenation
- C. Hydrolysis
- D. Saponification
Answer, explanation and textbook page: open in the app.
8.What would be the solubility of compared to ?
- A. Less soluble in water
- B. More soluble in water
- C. The same solubility in water.
- D. More soluble in a non-polar solvent such as dichloroethane.
Answer, explanation and textbook page: open in the app.
9.Which of the following gases is manufactured using the Haber process?
- A. Ammonia
- B. Nitric oxide
- C. Nitrogen
- D. Nitrogen dioxide
Answer, explanation and textbook page: open in the app.
10.Which one of the mixture of the following pairs will NOT give a buffer solution?
- A. $\mathrm{HCN}$ and $\mathrm{NaCN}$
- B. $\mathrm{NH_3}$ and $\mathrm{NH_4Cl}$
- C. $\mathrm{H_3PO_4}$ and $\mathrm{KH_2PO_4}$
- D. $\mathrm{HNO_3}$ and $\mathrm{NaNO_3}$
Answer, explanation and textbook page: open in the app.
11.Which one of the following is TRUE for salts formed from strong acids and strong bases?
- A. No hydrolysis takes place.
- B. Produces ions that are proton donors.
- C. Produces ions which are proton acceptors.
- D. Depends on the pKa and pKb of the parent acids and bases, respectively.
Answer, explanation and textbook page: open in the app.
12.Which of the following metals is NOT obtained by commercial electrolytic process?
- A. Ag
- B. Al
- C. Cu
- D. Na
Answer, explanation and textbook page: open in the app.
13.Which of the following metals has the highest electrical and thermal conductivities?
- A. Ag
- B. Co
- C. Cu
- D. Ni
Answer, explanation and textbook page: open in the app.
14.Enthalpy is defined as the heat content of the system at constant:
- A. Heat
- B. Moles
- C. Pressure
- D. Volume
Answer, explanation and textbook page: open in the app.
15.Which of the following elements is the second most abundant element in the earth's crust?
- A. Aluminium
- B. Iron
- C. Oxygen
- D. Silicon
Answer, explanation and textbook page: open in the app.
16.What is the number of significant figures in 0.0030050?
- A. 4
- B. 5
- C. 7
- D. 8
Answer, explanation and textbook page: open in the app.
17.Which of the following properties of a substance does NOT represent an intensive physical property?
- A. Boiling point
- B. Colour
- C. Density
- D. Volume
Answer, explanation and textbook page: open in the app.
18.What is the mass of one molecule of water?
- A. $3.0\times10^{-23}\,\text{g}$
- B. $1.8\times10^{-23}\,\text{g}$
- C. 0.0003g
- D. 18.0g
Answer, explanation and textbook page: open in the app.
19.Which of the following quantum number (s) is (are) related to the size and energy of an electron in a hydrogen atom?
- A. n
- B. n,l
- C. n,l,m
- D. n,l,m,s
Answer, explanation and textbook page: open in the app.
20.An electron has a spin quantum number, s = +1/2 and a magnetic quantum number, . In which of the following orbital will it NOT be present?
- A. S-orbital
- B. P-orbital
- C. d-orbital
- D. f-orbital
Answer, explanation and textbook page: open in the app.
21.Which of the following molecules has a trigonal bi pyramidal structure?
- A. $\mathrm{PCl_5}$
- B. $\mathrm{IF_5}$
- C. $\mathrm{ICl_4^-}$
- D. $\mathrm{BrF_5}$
Answer, explanation and textbook page: open in the app.
22.Which of the following represents the general configuration of the transition elements?
- A. $ns^2np^6$
- B. $ns(n-1)d$
- C. $ns(n-2)f$
- D. $ns^2np^6(n-1)d^{10}$
Answer, explanation and textbook page: open in the app.
23.The total number of electrons participating in the bond formation of carbonate anion, in the molecule of carbonic acid are:
- A. 16
- B. 10
- C. 8
- D. 5
Answer, explanation and textbook page: open in the app.
24.Which of the following crystals possess high electrical and thermal conductivities?
- A. Ionic crystals
- B. Metallic crystals
- C. Molecular crystals
- D. Covalent network crystals
Answer, explanation and textbook page: open in the app.
25.What is the valid rate expression for the following reaction? (Δ[H ])/Δt 2 □(Δ[H O])/Δt 2 □(Δ[NO])/Δt (Δ[N ])/Δt 2
- A. 1/2 ?
- B. -1/2
- C. -1/2
Answer, explanation and textbook page: open in the app.
26.Which of the following statements is TRUE about equilibrium reaction?
- A. No more reactants are transformed into products.
- B. There are equal amounts of reactants and products.
- C. The rate constant for the forward reactions equals that of the reverse reaction.
- D. The rate for the forward reactions equals that of the reverse reactions.
Answer, explanation and textbook page: open in the app.
27.Three gases are in equilibrium in a closed chamber sealed with a piston. The following equilibrium is established: $2\mathrm{NH_3}(\mathrm{g}) \rightleftharpoons \mathrm{N_2}(\mathrm{g}) + 3\mathrm{H_2}(\mathrm{g})$ What will happen if the piston is pushed into the chamber?
- A. The mole fraction of $\mathrm{N_2}$ increases.
- B. The mole of $\mathrm{N_2}$ decreases.
- C. The mole fraction of $\mathrm{N_2}$ remains the same.
- D. The mole fraction of $\mathrm{N_2}$ increases and then decreases.
Answer, explanation and textbook page: open in the app.
28.Which of the following reactions will produce an akyl carboxylic acid?
- A. Heating a methyl ketone with acid and iodine.
- B. Reacting an alkyl halide with hydrogen gas and platinum.
- C. Reacting an alcohol with ozone.
- D. Oxidation of a primary alcohol with hot permanganate or chromate.
Answer, explanation and textbook page: open in the app.
29.Which of the following statements is NOT TRUE?
- A. Naturally derived soaps consists of a soluble salt of a long chain fatty acid.
- B. Triacylglycerols are esters of glycerol and long chain carboxylic acids.
- C. Long chain carboxylic acids are also known as fatty acids.
- D. The major acidic component of vinegar is formic acid.
Answer, explanation and textbook page: open in the app.
30.What is the name of triacylglycerol(triglycerides) that is solid at room temperature?
- A. Lecithin
- B. Fat
- C. Wax
- D. Oil
Answer, explanation and textbook page: open in the app.
31.Which of the following is the most important type of solute-solvent interaction in a solution of n- butanol in water?
- A. Dispersion
- B. Ion-dipole
- C. Dipole-dipole
- D. Hydrogen bonding
Answer, explanation and textbook page: open in the app.
32.What is the product of the hydrolysis of easters in the presence of a mineral acid catalyst?
- A. Alcohol
- B. Carbon dioxide
- C. Ether
- D. Ketones
Answer, explanation and textbook page: open in the app.
33.To which organic functional group does the following molecular representation, i.e, belong? ( and represent different alkyl chains)
- A. Amides
- B. Aldehyde
- C. Ethers
- D. Organic acid
Answer, explanation and textbook page: open in the app.
34.What is the quantity of water, in mL, required to prepare $0.5\,\mathrm{M}$ of $\mathrm{HCl}$ from a concentrated solution of $3.5\mathrm{M}$ in 50 mL is?
- A. 50mL
- B. 100mL
- C. 300mL
- D. 350mL
Answer, explanation and textbook page: open in the app.
35.What is the equivalent weight of $\mathrm{HNO_3}$, as an oxidizing agent, in the following balanced reaction? $3\mathrm{Fe^{2+}} + 4\mathrm{H^+} + +\mathrm{NO_3^-} \longrightarrow 3\mathrm{Fe^{3+}} + \mathrm{NO} + 2\mathrm{H_2O}$
- A. 10.5
- B. 15.75
- C. 21.00
- D. 31.50
Answer, explanation and textbook page: open in the app.
36.Given the following equilibria and equilibrium constant: ( I ) ; K = 1.80 × 10 a −5 H CO + H O ⇌H O + HCO 2 3 2 3 + −3 K = 4.20 × 10 a −7 ( II ) ; ( III ) NH + H O ⇌H O + NH 4 + 2 3 + 3 K = 5.6 × 10 a −10 HCOOH + H O ⇌H O + COOH 2 3 + − ; ( IV ) ; K = 1.80 × 10 a −4 What is the strength of the acids in DECREASING order?
- A. I, IV, II and III
- B. II, III, IV and I
- C. III, II, I and IV
- D. IV, I, II and III
Answer, explanation and textbook page: open in the app.
37.Given the reaction: $\mathrm{H_2PO_4^- + H_2O \rightarrow H_3O^+ + HPO_4^{2-}}$ Which of the following represents a conjugate acid base pair?
- A. $\mathrm{H_2PO_4^-}$ and $\mathrm{H_2O}$
- B. $\mathrm{H_2PO_4^-}$ and $\mathrm{HPO_4^{2-}}$
- C. $\mathrm{H_2PO_4^-}$ and $\mathrm{H_3O^+}$
- D. $\mathrm{H_2O}$ and $\mathrm{H_2PO_4^{2-}}$
Answer, explanation and textbook page: open in the app.
38.Which of the following statements is TRUE about colligative properties?
- A. Both vapour pressure and freezing point increase when a non-volatile solute is added to a solvent.
- B. Both freezing point and boiling point increase when a non-volatile solute is added to a solvent.
- C. Both vapour pressure and boiling point decrease when a non-volatile solute is added to a solvent.
- D. Colligative properties depend only upon the number of solute particles in a solution and not upon their identity.
Answer, explanation and textbook page: open in the app.
39.What is the pH of 0.005 M solution of $\mathrm{Ca(OH)_2}$?
- A. 2.3
- B. 10
- C. 12
- D. 14
Answer, explanation and textbook page: open in the app.
40.How many kilo joules of heat are absorbed when 20 g of NaCl(s) is decomposed in to Na(s) and (g) at constant pressure according to the following reaction? 2Na(s) + Cl (g) →2NaCl(s) ΔH = 2 −821.8 kl
- A. -281.0
- B. -140.5
- C. +140.5
- D. +281.0
Answer, explanation and textbook page: open in the app.
41.In the electroplating of nickel from a solution containing ion, what will be the weight of the metal deposited on the cathode by a current of 8 A flowing for 500 minutes?
- A. 73g
- B. 103g
- C. 117.4g
- D. 145g
Answer, explanation and textbook page: open in the app.
42.A 1M solution of is placed in a beaker with a strip of Cu metal. A 1M of is placed in a second beaker with a strip of Sn metal. The two beakers are then connected by a salt bridge and the two metal electrodes are connected by wires to a voltmeter. Which of the following electrodes serves as the anode and E Cu /Cu = 0.34V 0 2+ E Sn /Sn = 0.14V 0 2+ which electrode gains mass? Given that and
- A. Anode, Sn, Sn electrode gains mass.
- B. Anode, Sn, Cu electrode gains mass.
- C. Anode, Cu, Sn electrode gains mass.
- D. Anode, Cu, Cu electrode gains mass.
Answer, explanation and textbook page: open in the app.
43.Which of the following metal alloys does NOT contain tin?
- A. Brass
- B. Bronze
- C. Pewter
- D. Plumber's solde
Answer, explanation and textbook page: open in the app.
44.What structural feature is usually needed to present in order for an addition polymer to be produced?
- A. A carbon-carbon sigma bond.
- B. A carbon-oxygen pi bond.
- C. A carbon-oxygen sigma bond.
- D. A carbon-carbon pi bond.
Answer, explanation and textbook page: open in the app.
45.What are the raw materials required to synthesize nylon 6, 6, a specific king of nylon?
- A. Diacids
- B. Diamines
- C. Diacids and diamines
- D. Polyethylene
Answer, explanation and textbook page: open in the app.
46.Which of the following substances are added to natural rubber to toughen it?
- A. Calcium
- B. Carbon
- C. Nitrogen
- D. Sulphur
Answer, explanation and textbook page: open in the app.
47.What is the quantity of heat required to raise the temperature of 80g of ethanol from to ? (specific 2.46 Jg K −1 −1 heat of ethanol = )
- A. 2.46kJ
- B. 4.0kJ
- C. 9.84kJ
- D. 18.68kJ
Answer, explanation and textbook page: open in the app.
48.Consider the following gaseous reaction at 250C: CH (g) + 20 (g) →CO (g) + 2H O(g) ΔH = 4 2 2 2 −802 kJ CH 4 Which energy change would occur if 3.2 moles of is completely combusted? 2.57 × 103 2.57 × 102
- A. kJ will be released.
- B. kJ will be absorbed. 6.43 × 103 6.43 × 103
- C. kJ will be released.
- D. kJ will be absorbed.
Answer, explanation and textbook page: open in the app.
49.What is the number of chloride ions ($\mathrm{Cl^-}$) present in $1.0 \times 10^{-5}\,\text{mol}$ of $\mathrm{AlCl_3}$?
- A. $1.80 \times 10^9$
- B. $6.02 \times 10^{18}$
- C. $6.02 \times 10^{23}$
- D. $6.02 \times 10^{28}$
Answer, explanation and textbook page: open in the app.
50.Which of the following is the most important ingredients used for production of DAP fertilizer?
- A. Ammonia and phosphoric acid.
- B. Nitric acid, urea and phosphoric acid.
- C. Phosphoric acid, urea and ammonia.
- D. Sulphuric acid, ammonia and urea.
Answer, explanation and textbook page: open in the app.
51.Which of the following bio molecules forms a zwitterions at higher or lower PH?
- A. Cellulose
- B. Glucose
- C. Protein
- D. Starch
Answer, explanation and textbook page: open in the app.
52.Which of the following form of synthetic rubbers can be vulcanized to greatly enhance its mechanical strength?
- A. Neoprene
- B. Isoprene
- C. Styrene-butadiene rubber
- D. Butyl rubber
Answer, explanation and textbook page: open in the app.
53.What is the range in the number of carbon atom of the monosaccharides that are found in nature?
- A. 3 to 7
- B. 4 to 10
- C. 4 to 12
- D. 5 to 12
Answer, explanation and textbook page: open in the app.
54.What are the two principal polysaccharide forms of starch?
- A. Aldohexose and ketopentose.
- B. Amylose and amylopectin.
- C. Maltose and cellobiose.
- D. Sucrose and lactose.
Answer, explanation and textbook page: open in the app.
55.What is the Kelvin scale (K) corresponding to the temperature readings when the degree Celsius ( ) is identical F 0 to the degree Fahrenheit ( )?
- A. 0 k
- B. 37 k
- C. 233 k
- D. 273 k
Answer, explanation and textbook page: open in the app.
56.What is the wavelength associated with an electron of mass, $m = 9.11 \times 10^{-28}\,\text{g}$, travelling at 40% of the velocity of light?
- A. $6.06 \times 10^{-15}\,\text{m}$
- B. $2.42 \times 10^{-15}$
- C. $6.06 \times 10^{-12}\,\text{m}$
- D. $2.42 \times 10^{-11}\,\text{m}$
Answer, explanation and textbook page: open in the app.
57.The quantum numbers listed below are meant for four different electrons in an atom: I. II. III. IV. = 1 0, m = s −1/2 When these sets of quantum numbers are arranged in order of increasing energy, one may get:
- A. I < II < III< IV
- B. I < III < II < IV □
- C. II < I < IV < III
- D. IV < III < II < I
Answer, explanation and textbook page: open in the app.
58.Which of the following hybrid orbitals is favouring the formation of trigonal bipyramidal?
- A. $\mathrm{sp^3d}$
- B. $\mathrm{sp^3}$
- C. $\mathrm{sp^3d^2}$
- D. $\mathrm{sp^3d^3}$
Answer, explanation and textbook page: open in the app.
59.Which one of the following molecules/molecular ions is paramagnetic according to the molecular orbital theory?
- A. $\mathrm{O_2^{2-}}$
- B. $\mathrm{O_2}$
- C. $\mathrm{F_2}$
- D. $\mathrm{O_2^{2+}}$
Answer, explanation and textbook page: open in the app.
60.For the reaction: the following experimental results were obtained: mol L s −1 −1 Experiment [A] [B] Rate ( ) 1 0.50 0.50 0.300 2 0.50 0.25 0.075 3 0.25 0.25 0.075 What is the value of the rate constant? L S −1 −1 L S −1 −1
- A. 0.6 mol
- B. 0.6 L S −1 −1 mol S −1 −1
- C. 1.2
- D. 2.4
Answer, explanation and textbook page: open in the app.
61.If a piece of aluminium (Al) foil measuring 24 cm by 31 cm has a mass of 10.35 g, (density of Al = $2.70\,\text{gcm}^{-3}$). What is the thickness of the foil in millimetres?
- A. $5.15\times10^{-3}$
- B. $5.15\times10^{-2}$
- C. 3.833
- D. 744
Answer, explanation and textbook page: open in the app.
62.Which of the following molecules has a dipole moment?
- A. XeF$_4$
- B. H$_2$S
- C. SO$_3$
- D. CH$_4$
Answer, explanation and textbook page: open in the app.
63.Which of the following reactions will convert carboxylic acids to primary amines?
- A. Decarboxylation with HBr and peroxide, then reaction of the alkyl bromide with ammonia.
- B. Reduction of the acid to the alcohol with NaOH/ formaldehyde then reaction with ammonium chloride and heat.
- C. A two-step conversion, first to the amide with ammonia and heat, and then by reduction with lithium aluminium hydride or hydrogen plus catalyst.
- D. Lactase fermentation in the presence of ammonia atmosphere
Answer, explanation and textbook page: open in the app.
64.A solution was prepared by adding 48g of methanol ( ) in to 81g of water ( ). What is the mole fraction of methanol in this solution?
- A. 0.25
- B. 0.75
- C. 1.5
- D. 4.5
Answer, explanation and textbook page: open in the app.
65.A solution was prepared by dissolving 3.75 g of pure hydrocarbon in 95.0g of cyclohexane. The boiling point of 80.70 C 0 81.45 C 0 pure cyclohexane was observed to be and that of the solution was . What is the approximate b 2.79 C/m 0 K molecular weight of the hydrocarbon? ( for cyclohexane = )
- A. 71.0g/mol
- B. 105g/mol
- C. 147g/mol
- D. 312g/mol
Answer, explanation and textbook page: open in the app.
66.To $0.2\,\mathrm{M}$ solution of a weak monoprotic acid, $\mathrm{HA}$, enough quantity of its sodium salt, $\mathrm{NaA}$, was dissolved to give a concentration of $0.2\,\mathrm{M}$ of the salt. What will be the acid concentration, $[\mathrm{H_3O^+}]$, in the final solutions? ($K_a$ of $\mathrm{HA}=1.80\times10^{-5}$)
- A. $3.60\times10^{-6}\,\mathrm{M}$
- B. $1.00\times10^{-5}\,\mathrm{M}$
- C. $1.80\times10^{-5}\,\mathrm{M}$
- D. $1.90\times10^{-3}\,\mathrm{M}$
Answer, explanation and textbook page: open in the app.
67.Gaseous petrol in a combustion system has done 375kJ of work during its expansion in the piston. Simultaneously, it absorbed 586 kJ of heat from the engine. What is the internal energy change during the process?
- A. +211kJ
- B. +961kJ
- C. -211kJ
- D. -961kJ
Answer, explanation and textbook page: open in the app.
68.Which of the following reactions is expected to have negative value of entropy change ($\Delta S$)?
- A. $\mathrm{C_6H_6(s)} + 6\mathrm{O_2(g)} \to 6\mathrm{CO_2(g)} + 6\mathrm{H_2O(l)}$
- B. $\mathrm{CaCO_3(s)} \to \mathrm{CaO(s)} + \mathrm{CO_2(g)}$
- C. $\mathrm{N_2O_4(g)} + \mathrm{Cl(g)} \to 2\mathrm{NOCl(g)} + \mathrm{O_2(g)}$
- D. $2\mathrm{SO_2(g)} + \mathrm{O_2(g)} \to 2\mathrm{SO_3(g)}$
Answer, explanation and textbook page: open in the app.
69.Consider the following unbalanced redox reaction in acidic solution: MnO + Fe →Mn + Fe 4 − 2+ 2+ 3+ Fe2+ what is the change in oxidation state for both the substances oxidized and reduced, and the coefficients of Mn2+ and , respectively after balancing?
- A. 2 and 7, and 2 and 5
- B. 3 and 2, and 5 and 1
- C. 1 and 5, and 5 and 1
- D. 2 and 5, and 5 and 2
Answer, explanation and textbook page: open in the app.
70.How many mL conc. $\mathrm{HNO_3}$ and how many mL of water are required to prepare 500mL of 0.1M $\mathrm{HNO_3}$ from a conc. 13M $\mathrm{HNO_3}$?
- A. 1mL $\mathrm{HNO_3}$ and 496.15 mL $\mathrm{H_2O}$.
- B. 3mL $\mathrm{HNO_3}$ and 500mL $\mathrm{H_2O}$.
- C. 3.85 mL $\mathrm{HNO_3}$ and 500mL $\mathrm{H_2O}$.
- D. 3.85 mL $\mathrm{HNO_3}$ and 496.15 mL $\mathrm{H_2O}$.
Answer, explanation and textbook page: open in the app.
71.What is the pH of an aqueous solution prepared to contain M sodium nitrite ( ) if the acid dissociation equilibrium constant, for nitrous acid ( ) is ?
- A. 3.1
- B. 5.1
- C. 6.0
- D. 7.3
Answer, explanation and textbook page: open in the app.
72.What reactions occur at the anode and cathode when an aqueous solution of is electrolyzed? red I. S O + 2e →2SO 2 8 2− − 4 2− O + 4H + 4e →2H O 2 + − 2 2H O + 2e →H + 2OH 2 − 2 − 2.01V II. 1.23V III. -0.83V Na + e →Na + − IV. -2.71V H 2 O 2 S O 2 8 2−
- A. at cathode and at anode.
- B. Na at cathode and at anode. H 2 S O 2 8 O 2
- C. at cathode and 2- at anode.
- D. Na at cathode and at anode.
Answer, explanation and textbook page: open in the app.
73.Which synthetic polymer is produced from caprolactam?
- A. Nylon -6
- B. Nylon 6, 10
- C. Teflon
- D. Terylene
Answer, explanation and textbook page: open in the app.
74.For the following hypothetical equation, in aqueous solution, what is the correct representation of the cell notation? A(s) + B (aq) _ A (aq) + B(s) 2+ 2+ A(s)∣A (aq)∣∣B (aq)∣B(s) 2+ 2+ B (aq)∣B(s)∣∣A (aq)∣A(s) 2+ 2+
- B. A (aq)(s)∣A(s)∣∣B(s)∣B (aq) 2+ 2+ B(s)∣B (aq)∣∣A (aq)∣A(s) 2+ 2+
Answer, explanation and textbook page: open in the app.

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