LW F6 Chem Mock Exam P1 1617
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F.6 Chemistry Paper I P.1 / 20 SKH LAM WOO MEMORIAL SECONDARY SCHOOL Mock Examination (2016-2017) F.6 Chemistry Paper 1 Date: 10/02/2017 (Friday) Time allowed: 2 hours 30 minutes Section A: Multiple-choice Questions (36 marks) 1. Which of the following statements concerning a PCl
5
molecule is/are correct? (1) Its shape is trigonal bipyramidal. (2) It is a polar molecular. (3) The number of bond pairs of electrons of P atom is 5. A. (1) only B. (2) only C. (1) and (2) only D. (1) and (3) only 2. A cation of a certain element has 22 electrons and a mass number of 55. If the charge on the cation is 3+, the number of neutrons in the cation is A. 19. B. 23. C. 25. D. 30. 3. 12.5 g of a hydrated metal sulphate was heated to constant mass. After cooling to room temperature, the residual anhydrous metal sulphate weighed 8.0 g. It is given that the formula mass of the anhydrous metal sulphate is 159.7. How many moles of water of crystallization are there in one mole of the hydrated sulphate? A. 2 B. 4 C. 5 D. 7 4. What volume of gas, measured at room temperature and pressure, would be formed from the decomposition of 15.0 g of sodium azide, NaN
3
? ( Molar volume of gas at room temperature and pressure = 24.0 dm
3
mol
-1
) A. 3.7 dm
3 B. 5.5 dm
3
C. 8.3 dm
3 D. 16.6 dm
3
5. Which of the following compounds contains dative covalent bond? A. OCl
2 B. CF
2
Cl
2
C. NBr
3 D. HNO
3
6. X
, Y
, and
Z
are three metals. X
can be extracted from its oxide by carbon reduction and Y
can be extracted by direct heating of its oxide. Z cannot be extracted by such methods. Which of the following statements is correct? A. Z
is the least reactive one. B. Y
is more reactive than X
. C. Y
should be discovered before Z
.
F.6 Chemistry Paper I P.2 / 20 D. X
is probably calcium. 7. There are five unlabelled test tubes containing 1.0 mol dm
–
3
of NH
4
Cl(aq), HNO
3
(aq), Na
2
CO
3
(aq), BaCl
2
(aq) and H
2
SO
3
(aq) respectively. Given that Solution 5 gave a white precipitate with each of Solutions 3 and 4, but had no reaction with Solutions 1 and 2. Which of the following observations is correct when mixing Solutions 3 and 4? A. Colourless gas bubbles are liberated. B. White precipitate forms. C. A chemical reaction occurs but does not have any visible change. D. No chemical reaction occurs. Direction: Questions 8 to 9 refer to the following information. 0.953 g of metal W was added to 25.0 cm
3
of 1 M H
2
SO
4
(aq) to form WSO
4
(aq) and H
2
(g). The resulting mixture was diluted to 250.0 cm
3
. 25.0cm
3
of the diluted solution was withdrawn and titrated against 0.07 M NaOH(aq) with an indicator. The mean titre was 22.60 cm
3
. 8. How many number of moles of H
2
SO
4
is present in the 250.0 cm
3
diluted solution? A. 7.91 x 10
-4
mol B. 1.582 x 10
-3
mol C. 7.91 x 10
-3
mol D. 0.791 mol 9. What is the relative atomic mass of W? A. 40.1 B. 55.8 C. 65.4 D. 87.6 10. Sulphur dioxide gas is converted into sulphate ions when it is bubbled into a solution containing aqueous manganate(VII) ions. One of the half equation involved is given below. MnO
4
-
(aq) + 8H
+
(aq) + 5e
-
→
Mn
2+
(aq) + 4H
2
O(l) How will the pH of the reaction mixture change as sulphur dioxide gas is bubbled at constant rate into a well-stirred solution of manganate(VII) ions until its colour just fades? A. a decrease B. a decrease then an increase C. an increase D. an increase then a decrease 11. Upon cracking, one molecule of the alkane C
12
H
26
gives ethene and propene in the ratio of 2:1 and an alkane X. What is the molecular formula of X? A. C
2
H
6 B. C
5
H
12
C. C
8
H
6 D. C
9
H
20
12. Which of the following reactions represent a propagation step in the reaction between bromine and ethane?
F.6 Chemistry Paper I P.3 / 20 A. (1) and (2) only B. (1) and (3) only C. (2) and (3) only D. (1), (2) and (3) 13. A compound has the following structure: Which of the following is the correct systematic name for this compound? A. 1,3-dibromo-1,2-dimethylpropan-2-ol B. 1,3-dibromo-2-methylbutan-2-ol C. 1,2-dimethyl-3-bromomethylpropan-2-ol D. 3-bromo-2-bromomethylbutan-2-ol 14. Buckminsterfullerene is the most commonly occurring fullerene molecule, found in small quantities in soot. Which statement about buckminsterfullerene is incorrect? A. Its relative molecular mass is 720. B. The carbon atoms in the molecule are each bonded to four neighbours. C. The molecule is composed of hexagons and pentagons of carbon atoms. D. Van der Waals
’
forces occur between molecules in the solid. 15. In which process are hydrogen bonds broken? A. H
2
(l) →
H
2
(g) B. NH
3
(l) →
NH
3
(g) C. 2HI(g) →
H
2
(g) + I
2
(g) D. CH
4
(g) →
C(g) + 4H(g) 16. Consider the following diagram about the set-up of a simple chemical cell.
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F.6 Chemistry Paper I P.4 / 20 According to the above diagram, which of the following statements is correct? A. The lead electrode is the positive pole. B. The lead electrode will dissolve. C. Sugar solution can be used as the electrolyte. D. Lead is at a higher position in the electrochemical series than metal Y. 17. Consider the reaction between chlorine and hot concentrated potassium hydroxide solution: 2Cl
2
(g) + 6KOH(aq) →
5KCl(aq) + KClO
3
(aq) + 3H
2
O(aq) Which of the following statements is/are correct? (1) The reaction is a redox reaction, in which KOH acts as the reducing agent. (2) The oxidation number of chlorine decreases from 0 to -1. (3) The oxidation number of chlorine increases from 0 to +5. A. (2) only B. (3) only C. (1) and (2) only D. (2) and (3) only 18. Which of the following statements about salt bridge is/are correct? (1) It allows the electrons to pass through so that the circuit is completed. (2) It can be prepared by soaking a filter paper with saturated silver iodide solution. (3) It can speed up the redox reaction occurring in the 2 half cells. A. (1) only B. (1) and (2) only C. (2) and (3) only D. None of the above 19. Consider the following fuel cell.
F.6 Chemistry Paper I P.5 / 20 Which of the following statements about the above fuel cell is/are correct? (1) Reduction occurs at electrode X. (2) The fuel cell is environmentally friendly. (3) Both H
2
and O
2
are used as fuels in the cell. A. (2) only B. (1) and (2) only C. (2) and (3) only D. (1), (2) and (3) 20. In an experiment, 2.5 cm
3
portions of 1M NaOH solution are added to 25 cm
3
of 1M HCl solution every 0.5 minute until 25 cm
3
of NaOH is added. The temperature of the mixture is measured immediately after each addition. Which of the following graphs represents the relationship between the temperature of the mixture and the volume of NaOH added? 21. The standard enthalpy changes of formation of some substances are shown below: Substance
H
o
f
(kJ mol
-1
) Mn
2
O
3
(s) -971 CO(g) -111 CO
2
(g) -394 Manganese can be extracted from Mn
2
O
3
by reduction with carbon monoxide. Mn
2
O
3
(s) + 3CO(g) →
2Mn(s) + 3CO
2
(g) What is the standard enthalpy change of this extraction? A. -544 kJ mol
-1 B. -122 kJ mol
-1
C. +122 kJ mol
-1 D. +544 kJ mol
-1
22. In which of the following methods are sodium hydroxide produced? (1) Adding sodium to water (2) Electrolysis of concentrated sodium chloride solution using graphite as electrodes (3) Electrolysis of dilute sodium chloride solution using graphite as electrodes (4) Adding potassium hydroxide solution to sodium chloride solution A. (1) and (2) only B. (1) and (4) only C. (2) and (3) only D. (1), (2), (3) and (4)
F.6 Chemistry Paper I P.6 / 20 Directions:
A. Both statements are true and the 2nd statement is a correct explanation of the 1st statement. B. Both statements are true but the 2nd statement is NOT a correct explanation of the 1st statement. C. The 1st statement is false but the 2nd statement is true. D. Both statements are false. 1st statement 2nd statement 23. Polystyrene is an addition polymer. Polystyrene is a thermoplastic. 24. The pH of a solution can be a negative value. The concentration of hydrogen ions in a solution can be larger than 1.0 M. 25. The set-up shown below is used in an experiment to study the rate of the reaction: CaCO
3
(s) + 2HCl(aq) →
CaCl
2
(aq) + H
2
O(l) + CO
2
(g) The conical flask is shaken to overturn the vial in order to start the reaction. The initial rate of the reaction with respect to the gas liberated is determined. The experiment is then repeated with only one of the conditions changed while the others remain unchanged. Under which of the following situations would the initial rate be the same as that in the original experiment? A. using 10 cm
3
of 1 mol dm
-3
HCl(aq) B. using 5 cm
3
of 2 mol dm
-3
HCl(aq) C. using 5 cm
3
of 1 mol dm
-3
HCl(aq) which is preheated to 50
o
C D. using powdered CaCO
3
(s) of the same mass 26. The curve Y and the value E
a
represent the distribution of energies of the molecules and the activation energy for an uncatalysed gaseous reaction. A
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F.6 Chemistry Paper I P.7 / 20 What is a possible outcome if the reaction is catalysed? The distribution energies will be given by Activation energy will be given by A. X V B. Y V C. Y W D. Z W 27. Consider the following reaction: C
4
H
10
(g) + Cl
2
(g) →
C
4
H
9
Cl(l) + HCl(g) Which of the following changes will increase the rate of reaction? (1) Increase in pressure (2) Increase in temperature (3) Removal of HCl(g) A. (1) and (2) only B. (1) and (3) only C. (2) and (3) only D. (1), (2) and (3) 28. Ethoxyethane, C
2
H
5
OC
2
H
5
, is the most well known of a class of compounds called ethers. Ethers have the general formula R
1
-O-R
2
where R
1
and R
2
are hydrocarbon groups. What is the lowest number of carbon atoms a non-cyclic ether molecule needs to have a chiral carbon atom? A. 4 B. 5 C. 6 D. 7 29. Consider the following reaction between carbon dioxide and hydrogen. CO
2
(g) + H
2
(g) ⇌
H
2
O(l) + CO(g) The values of K
c
at different temperatures for the reaction are as follows: Temperature K
c
227
o
C 7.76 x 10
-3
427
o
C 0.123 627
o
C 0.6 Which of the following statements must be correct? A. H
2
(g) and CO
2
(g) are less stable than H
2
O(l) and CO(g). B. The forward reaction is exothermic. C. The reaction goes almost to completion at a high temperature. D. The forward reaction is favoured by a high temperature. 30. A 36.8 g sample of N
2
O
4
was heated in a closed flask of volume 16.0 dm
3
. An equilibrium was established at a constant temperature according to the following equation. N
2
O
4
(g) ⇌
2NO
2
(g) The equilibrium mixture was found to contain 0.16 mol of N
2
O
4
.
F.6 Chemistry Paper I P.8 / 20 Calculate the equilibrium constant for the reaction. A. 3 mol dm
-3 B. 1.44 mol dm
-3
C. 0.96 mol
dm
-3 D. 0.09 mol dm
-3
31. The structure of polymer X is shown below: Which of the following statements about X is correct? A. It possesses a ketone functional group. B. It can undergo degradation in an acidic environment. C. It has a giant covalent network structure. D. It has a sharp melting point. 32. Consider the following compounds: Which of these compounds can be used as active ingredients of detergents? A. (1) and (2) only B. (1) and (3) only C. (2) and (3) only D. (1), (2) and (3) 33. In which of the following reactions, is/are the transition metal species NOT acting as a catalyst? (1) action of acidified MnO
4
-
(aq) on SO
3
2-
(aq) at room temperature (2) action of Ni(s) on a mixture of H
2
C=CH
2
(g) and H
2
(g) at high temperature (3) action of Pt(s) on a mixture of CO(g) and O
2
(g) at high temperature A. (1) only B. (2) only C. (1) and (3) only D. (2) and (3) only 34. The elements, sodium to chlorine, in the third period of the periodic table shows a gradual change in properties. Which of the following changes is/are correct?
F.6 Chemistry Paper I P.9 / 20 (1) Their electronegativity increases. (2) Their oxides change from acidic to basic. (3) Their chlorides changes from ionic to covalent. A. (1) only B. (2) only C. (1) and (3) only D. (2) and (3) only Directions:
A. Both statements are true and the 2nd statement is a correct explanation of the 1st statement. B. Both statements are true but the 2nd statement is NOT a correct explanation of the 1st statement. C. The 1st statement is false but the 2nd statement is true. D. Both statements are false. 1st statement 2nd statement *35. All alcohols can turn acidified potassium dichromate solution from orange to green. Some alcohols are oxidized to carbonyl compounds and some are oxidized to form carboxylic acids. 36. The structural formula H
2
C=CF
2
can represent two different compounds. The rotation of the CF
2
group relative to the CH
2
group in H
2
C=CF
2
is restricted by the C=C bond. * deleted END OF SECTION A Section B: Conventional Questions (84 marks) Answer ALL questions. Write your answers in the space provided. 1. Consider compounds, H
2
O and F
2
O. (a) Draw an electron diagram, showing the outermost electrons only, for F
2
O. (1 mark) (b) A student gives a statement about F
2
O molecule as shown below. ‘
F
2
O is a non-polar molecule as the two F-O bonds are non-polar.
’
Explain whether the statement is correct or not. (3 marks)
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F.6 Chemistry Paper I P.10 / 20 (c) Which compound would you expect to have a higher boiling point? Explain your answer. (2 marks) *2. Graphite and diamond are two pure forms of carbon but they show some contrasting properties. Choose one such property and explain the difference in terms of structure and bonding. (5 marks)
F.6 Chemistry Paper I P.11 / 20 3. Dry hydrogen is passed over two heated oxides X
and Y
of the same metal M
as shown below. (a) Suggest why it is necessary to burn the excess hydrogen gas in the set-up. (1 mark) (b) It is found that 5.4 g of X
and 6.0 g of Y
are both reduced to 4.2 g of M
. If the empirical formula of Y
is M
2
O
3
, work out the empirical formula of X
. (4 marks) (c) A strip of metal M
is placed in a test tube containing copper(II) sulphate solution. (2 marks) (i) Name the reaction that occurs. (ii) Give one possible observation in the reaction. 4. Jenny used the following set up to study the electrolysis of a dilute sulphuric acid solution. excess H
2
burns dry hydrogen oxide X oxide Y heat
F.6 Chemistry Paper I P.12 / 20 Before the electrolysis, Jenny carried out titration to determine the concentration of the sulphuric acid using standard 0.50 M sodium hydroxide solution. On the average, 24.45 cm
3
sodium hydroxide solution was required to react with 25.00 cm
3
sulphuric acid. (a) Suggest a suitable indicator for the titration and state the observation at the end point of the reaction. (2 marks) (b) Calculate the initial concentration of the sulphuric acid. (3 marks) (c) The electrolysis was then carried out for several minutes and 25 cm
3
of hydrogen gas was collected in syringe A. (2 marks) (i) What is the polarity of electrode X? 8. (c) (ii) Calculate the number of moles of hydrogen gas collected. (Molar volume of gas at room temperature and pressure = 24.0 dm
3
mol
-1
) *(d) According to the result, Jenny made the following prediction. “
As H
+
(aq) ions are discharged to give the hydrogen gas, the concentration of the acid will decrease continuously when the electrolysis goes on.
”
Comment on Jenny
’
s predication and give appropriate equations when necessary. (5 marks)
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F.6 Chemistry Paper I P.13 / 20 5. Given the following thermochemical data at 298 K: Compound
H
o
combustion
/kJ mol
-1
H
o
formation
/kJ mol
-1
Propene (g) -2058 --- Propane (g) -2220 --- Water (l) --- -285.8 (a) What is ‘
standard enthalpy change of combustion
’
? (1 mark) (b) With the help of an appropriate enthalpy cycle, calculate the enthalpy change involved in the hydrogenation of propene to propane. (3 marks)
F.6 Chemistry Paper I P.14 / 20 5. (c) After some lessons in organic chemistry, a student remarked, ‘
Alkanes are more stable than alkenes, therefore alkanes do not react with chlorine but alkenes do.
’
With the help of the results above and your chemical knowledge, explain whether the remark made by the student is correct or not. (3 marks) 6. The labels of three bottles of white solids are lost. The solids involved are CaCO
3
(s), CaCl
2
(s) and Ca(NO
3
)
2
(s). Suggest how the identity of the solid in each bottle can be determined. You can use not more than one chemical test in the identification process. (4 marks) 7. A syringe containing sulphur dioxide and a 6-well plate are placed in a zip-lock plastic bag as shown below:
F.6 Chemistry Paper I P.15 / 20 The syringe is pushed to eject the sulphur dioxide gas. (a) What would happen to the pH paper? Explain your answer. (2 marks) (b) The aqueous bromine turns from yellow to colourless. Write ionic half equations to show the reaction involved. (2 marks) (c) What would be observed in the iron(III) sulphate solution? (1 mark) (d) What role does sulphur dioxide gas take in the reactions mentioned in (b) and (c)? Explain your answer. (2 marks) (e) State ONE advantage of doing the experiment this way rather than using test tubes of sulphur dioxide gas. (1 mark) 8. (a) The graph below shows the variation in melting points for the period three elements in the Periodic Table. (i) Why are these elements placed in period three of the Periodic Table? (1 mark)
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F.6 Chemistry Paper I P.16 / 20 (ii) Explain why S has a higher melting point than P. (2 marks) (b) Compare the reactions of Na
2
O and Cl
2
O with water. Write equation(s), with state symbols, where appropriate. (4 marks) 9. Under same experimental conditions, the same mass of ‘
expired
’
and ‘
fresh
’
calcium granules were separately put into water as shown in the diagrams below. The ‘
expired
’
calcium granules have been exposed in air for a long time, while the ‘
fresh
’
calcium granules are newly bought. (a) Write a chemical equation for the reaction involved. (1 mark) (b) Suggest why less gas was collected in the set-up of Diagram 1 than that of Diagram 2. (1 mark)
F.6 Chemistry Paper I P.17 / 20 The rate of reaction for the ‘
fresh
’
calcium granules with water is to be studied further. (c) Draw a labeled diagram for the set-up which can be used to monitor the rate of the reaction. (2 marks) (d) Sketch a rate curve that shows the results of the experiment. (2 marks) 10. A dynamic equilibrium is established when propanoic acid is dissolved in water at 298 K. CH
3
CH
2
COOH(aq) ⇌
CH
3
CH
2
COO
-
(aq) + H
+
(aq) (a) What is a dynamic equilibrium? (1 mark) (b) At 298 K, the pH of 0.050 M propanoic acid is 3.10. Calculate the concentration of H
+
(aq) in the acid. (1 mark) (c) Calculate the equilibrium constant, K, for propanoic acid at 298 K. (2 marks)
F.6 Chemistry Paper I P.18 / 20 (d) What change would occur to the equilibrium constant, K, if 2 drops 0.05 M dilute sodium hydroxide solution is added to the above equilibrium system? Explain your answer. (1 mark) (e) At 338 K, the pH of 0.05 M propanoic acid is 2.8. Explain what information about the equilibrium can be interpreted from this experimental result. (2 marks) 11. An alkene A, C
4
H
8
, upon reaction with reagent B gives two products W and X with the same molecular formula C
4
H
9
Br. After separation, W and X are allowed to have the same reactions. The reaction scheme involved is shown below. Step 1
reagent B
NaOH(aq)
Oxidation
Y
Z
S
T
X
W
A
Oxidation
reagent D
NaOH(aq)
reagent D
(a) What are reagent B and reagent D? (2 marks) (b) Name the type of reaction involved in step 1. (1 mark) (c) Give the structural formulae of W, X, Y, Z, S and T. (3 marks) Compound Structural formula Compound Structural formula W X Y Z S T
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F.6 Chemistry Paper I P.19 / 20 (d) Which compound, W or X, is the major product formed from A in step 1? (1 mark) (e) What type of isomerism does compound Y show? Why do you think so? (2 marks) 12. (a) Outline a synthetic route, with no more than three steps, to accomplish the following conversion. For each step, give the reagent(s), reaction conditions (as appropriate) and structure of the organic product. (3 marks) (b) CH
3
CH
2
COOH CH
3
CH
2
CHO (i) Briefly explain why the above proposed reaction cannot lead to the target molecule. (1 mark) (ii) Using the same starting molecule, outline a feasible synthetic route to obtain the target molecule, with no more than three steps. In each step, give the reagent(s) used, the conditions required and structure of the organic product. (2 marks) END OF SECTION B LiAlH
4
, H
3
O
+
F.6 Chemistry Paper I P.20 / 20 END OF PAPER
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How many lone pairs are around the central atom?
What is the ideal angle between the bromine-oxygen
bonds?
Compared to the ideal angle, you would expect the
actual angle between the bromine-oxygen bonds to
be ...
0
口。
(choose one)
X
3
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A hypothetical molecule has the following formula XY2. The B-P bonds are polar covalent, with B being most electronegative, however the molecule itself is non polar. What molecular geometry(ies) are possible for this molecule. Use 3-D drawings to explain.
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For molecule CN2 2- , give Lewis structure, Valence Shell Electron pairs, bonding electron pairs, nonbonding electron pairs, VSEPR formula, bond angle, and molecular geometry (shape).
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In terms of the bonds present, explain why acetic acid, CH3CO2H, contains two distinct types of carbon-oxygen
bonds, whereas the acetate ion, formed by loss of a hydrogen ion from acetic acid, only contains one type of carbon-
oxygen bond. The skeleton structures of these species are shown:
но
H
Н—с—с-о—н
H-C-C-
H.
H.
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ELECTRONIC STRUCTURE AND CHEMICAL BONDING
Predicting deviations from ideal bond angles
Consider the bromate (BrO3)
anion.
What is the central atom? Enter its emical symbol.
How many lone pairs are around the central atom?
What is the ideal angle between the bromine-oxygen
bonds?
Compared to the ideal angle, you would expect the
actual angle between the bromine-oxygen bonds to
be ...
0
口。
(choose one)
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Determine whether each molecule is polar or nonpolar: (a) H 2O; (b) CO 2.
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Imagine you are a CHML 201 instructor. One of your students asks “Why is water, H2O, a bent molecule (in other words, why is water’s molecular shape bent with an angle of ~105o)? Why isn’t water a linear molecule?” Answer the student’s question clearly, completely, and in detail – starting from the electronic structure of H and O atoms. A Periodic Table and a Table of Electronegativity values are given above.
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Answer the questions in the table below about the shape of the phosphorus trifluoride (PF3) molecule.
How many electron groups are around the central phosphorus
atom?
Note: one "electron group" means one lone pair, one single bond,
one double bond, or one triple bond.
What phrase best describes the arrangement of these electron
groups around the central phosphorus atom?
(You may need to use the scrollbar to see all the choices.)
(choose one)
X
Ś
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Which of the following bonds are polar? C-O, Cl-Cl, O=O, N-H, C-H.(Electronegativites: C = 2.5, H = 2.1, Cl = 3.0, O = 3.5, N = 3.0). In the selected bonds indicatewhich direction the electron density is greatest.
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#74. With Lewis dot structures
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What is the shape and polarity for the molecule A3 - where A is a halogen?
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Draw a Lewis structure for the C4Hg molecule usıng the connectivity shown in the spacefillıng model in the window.
Gray = C; white = H; red = 0; blue = N; dark green = Cl; brown = Br; light green = F; purple = I; yellow = S; orange = P.
%3D
Use your drawing to answer the following questions.
The total number of electrons in C-H bonds =
The number of C-C single bonds =|
The number of C=C double bonds =
Previous
Next
The total number of unshared pairs
%3D
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Please help me answer these lab questions
Molecular-Models experiment
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Are all tetrahedral molecules NONpolar? If you say "no", write the formula of a
tetrahedral molecule that is polar.
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- 10arrow_forwardELECTRONIC STRUCTURE AND CHEMICAL BONDING Predicting deviations from ideal bond angles Consider the chlorite (C102) a anion. What is the central atom? Enter its chemical symbol. How many lone pairs are around the central atom? What is the ideal angle between the chlorine-oxygen bonds? Compared to the ideal angle, you would expect the actual angle between the chlorine-oxygen bonds to be... 0 0 (choose one) X 3 1/5arrow_forward1) Why is it important to understand the molecular geometry or shape of molecules and ions in chemistry? H2Se CCl4 CH2Cl2 HCN NH3Cl+ NH2- CH3COCH3 CH3COOH 2) Among the eight molecules and ions studied in this experiment, (a) which molecule(s) or ion(s) are polar, and which ones are non-polar? (b) What is the difference between polar and non-polar molecules or ions? (c) What two factors dictate the polarity of the molecule or ion?arrow_forward
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