Topic 1: Carbon and its compounds
PAPER PEN TEST
TIME: 40 Min Max marks:40.
1. Name the compound form heating ethanol at 443 K with excess of conc.H2SO4. 1
2. What happened when a small piece of sodium is dropped into ethanol ? 1
3. Write the chemical equation for the decarboxylation of ethanoic acid? 1
4. Give an example of esterification reaction. 1
5. Name the product obtained when ethanol is oxidized by either chromic anhydride or alkaline potassium permanganate. 1
6. Write the chemical equation repressing the preparation reaction of ethanol from ethane. 1.
7. Name the 2 elements which are present both in CNG and Petroleum 2
8. Draw the electronic dot structure of ethane molecule (C2H6) 2
9. Write the IUPAC name of the next homologous of CH3OHCH2CH3. 2
10.Define homologous series of organic compounds series of organic compounds ,Mention any two characteristics of homologous series. 2
11.Describe a chemical test to distinguish between ethanol and ethanoic acid. 2
12. Give the name of functional groups
(i)-CHO (ii) –C=0 2
13.Why does carbon form compounds mainly by covalent bonding ? 2
14.Give a chemical test to distinguish ethanol from ethanoic acid. 2
15 Allotropy is a property shown by which class: substances elements compounds or mixtures ? give one examples of allotropy. 2
16 . How may be the following be obtained from ethanol ? express giving chemical equations.
Ethyl ethanoate (ii) Sodium ethoxide. 2
17. Describe with chemical equation how ethanoic acid may be obtained from.
(i) Ethanol (ii) Methanol 2
18. Explain the cleansing action of soap 3
19.Distinguish between esterification and saponification reactions of organic compounds 3.
20 Explain the structure of graphite in term of bonding and give one property based on this structure. 3
21 Name the organic acid present in vinegar .write a chemical equation which represents the commercial method for the preparation of this acid from methanol. 3
HIGH ORDER THINKING SKILLS (HOTS) QUESTIONS:
Why the colour of potassium permangante disappers,if it is added to warm solution of ethanol.
An organic compound with molecular formula C2H4O2 produces brisk effervescence on addition of sodium carbonate /bicarbonate.
a .Identify the organic compound.
b. Name the gas evolved.
C. How will you test the gas evolved.
d. Write the chemical equation for the above reaction.
e. List two important uses of the above compound.
3.a.What are the various possible structure formulae of a compound having molecular formula C3H6O .
b. Also give the IUPAC names of the above possible compounds.
c.What is the similarity in these compounds?
4.A mixture of oxygen and ethyne is burnt for welding ,can you tell why a mixture of ethyne and air is not used .
5.Two carbon compound A and B have molecular formula C3H8 and C3H6 respectively. Which one of the two is most likely to show addition .justify your answer .Explain with the help of a chemical equation ,how an addition reaction is used in vegetable ghee industry.
6.1ml glacial acetic acid and 1ml of ethanol are mixed together in a test tube. Few drops of concentrated sulphuric acid is added in the mixture are warmed in a water bath for 5 min.
a.Name the resultant compound formed.
b.Represent the above change by a chemical equation .
c.What term is given to such a reaction.
d.What are the special characteristics of the compound formed.
7.An organic compound ‘X’with a molecular formula C2H6O undergoes oxidation in the presence of alkaline KMnO4 and forms the compound ‘Y’.
a. Identify ‘X’ and ‘Y’
B.Write your observation when the compound ‘X’ is made to react with compound ‘Y’ which
is used as a preservative for pickles.
Topic 1:Carbon and its compounds
1.Name the simplest hydrocarbon..
2.What is the general formula of alkynes.?
3.Name the carboxylic acid used as preservation
4.Name the product other than water formed on burning of ethanol in air.
5 Give the IUPAC name of the following compounds.
An aldehyde derived from ethane.
A ketone derived from butane.
A chloride derived from propane.
An alcohol derived from pentane.
1. Dilute acetic acid was added to the four test tubes containing the following chemical.
i.KOH ii.NaHCO3 iii. K2CO3 iv. NaCI
Brisk effervescence was observed in test tubes
a) i & ii b) ii & iii c) i& iv d) ii & iii
2. Which of the following solution of acetic acid in water can be used as vinegar used in pickles?
a) 5-10% b. 10-15% c.20-130% d.100%
3.The suffix used for naming an aldehyde is
a..ol b.al c.One d..ene
4.When acetic acid reacts with ethyl alcohol ,we add cons,H2SO4,its acts as……….and the
process is called…………………..
a)Oxidizing agent, saponification. b). Dehydrating agent, esterification c). reducing agent ,esterification.d).Acid & esterification.
5.2ml of ethanoic acid was taken in each of the three test tubes.A,B and C,and 2ml.4ml and 8ml water was added to them ,respectively .A clear solution is obtained in:
a. Test tube A only.
b.Test tubes A & B only.
c.Test tubes B and C only.
d. All the test tubes.
6.2 ml pf acetic acid was added in drops to 5ml of water it was noticed that:
a.The acid formed a separate layer on the top of water.
b.Water formed a separate layer on the top of the acid.
c.A clear and homogenous solution was formed.
d.A pink and clear solution was formed.
7.A few drops of ethanoic acid was added to solid sodium carbonate .The observation made was that
A hissing sound was evolved
Brown fumes evolved.
Brisk effervescence occurred.
A pungent smelling gas evolved.
8.Acetic acid , when dissolved in water, it dissociates into ions reversibly because it is a :
A. Weak acid B. strong acid. C. weak base. D. strong base.
9.Which of the following hydrocarbon can show isomerism?
a.C2H4 b. C2H6 c.C3H8 d.C4H10
10.Combustion of hydrocarbon is generally accompanied by evolution of
a. Heat b. Light c. both heat and light d. Electric current.
1.Compounds containing double and triple bonds.
2.A compound which is basic constituent of many cough syrups.
3.Very dilute solution of ethanoic acid.
4.A sweet smelling substance formed by the reaction of alcohol and carboxylic acids.
5 Gas released when sodium metal is dropped in ethanol.
6.The functional group present in methanol.
7.IUPAC name of alkene containing 3 carbon atoms.
8.The number of single covalent compounds present in pentane.
9.First member of homologous serious alkyne.
10. Simplest ketone.
11.Self linking property of carbon.
12.Product formed by dehydration of ethanol in conc. Sulphuric acid.
13.Alcohol whose intake in small quantities can be lethal.
14.Number of single covalent bounds in ammonia.
15.Type of reactions shown by alkanes.
1.To Study the saponification reaction for the preparation of soap in the laboratory using any vegetable oils.
2.Prepare soaps of different colours and fragrances.
CARBON AND ITS COMPOUNDS
3..Testing the hardness of water.
4..Collect information about artificial ripening of fruits by ethylene.
To prepare models of methane ,ethane,ethyne and benzene molecules using thermocols ,ball and match sticks.
TOPICS FOR DEBATE:
1.Role of esters in everyday life.
2. Condemning the use of alcohol as a social practice.
3.Use of biodegradable synthetic for cleansing purpose.
TOPIC 2: PERIODIC CLASSIFICATION OF ELEMENTS
Gist of the lesson:
Classification of elements:the arrangement of element in such manner that element with similar properties are grouped together while elements with dissimilar properties are separated .
Early attempt to classify elements:
He arranged the elements with similar properties in a group of three known as triad in such a manner that the atomic mass of the middle element was approximately the average of the other two elements
Only three triads were identified from the element known at that time .hence this classification was not useful.
NEWLAND’S LAW OF OCTAVES :
He arranged the element in the order of increasing atomic masses starting with hydrogen(least atomic mass ) and ended with thorium having atomic mass 56 . According to him ,the properties of every eighth element are similar to the first element . Iit was compared to music notation sa,re ,ga ,ma, pa ,da ,ni ,sa,and thus the name Newlands law of octaves(notes of music ).
1. It was applicable only for lighter element having atomic mass upto 40 amu ,i.e.upto calcium .
2. He believed that only 56 elements existed in nature but later on more element were discovered whose properties did not fit into Newland law of octaves.
3. Some elements having different properties were grouped together like cobalt and nickel have been placed with halogens .
Due to above limitations, Newland law of octave was rejected
MANDELEEV’S PERIODIC TABLE :
He arranged the elements in order of increasing atomic masses , similarity in physical and chemical properties of element . properties of hydrides and oxides of different element were studied and elements with similar properties were grouped together .
He classified the elements in table consisted of vertical columns called groups and horizontal rows called periods . there were 7 groups in table and group is subdivided into subgroups A and B except group 7 which has three sets of elements in 4th , 5th , 6th period.
LIMITATIONS OF MENDELEEV, PERIODIC TABLE :
1. Position of hydrogen was not assigned correctly .
2. No separate position has been given to isotopes of an element .
3. Some element having higher atomic mass are placed before the elements with lower atomic mass .
MODERN PERIODIC TABLE :
Mosely modified the Mandelleve’s periodic table by taking atomic number as the fundamental property instead of atomic mass.
Modern periodic table consists of 18 vertical columns known as group , and 7 horizontal rows known as periods .
Elements in group one are called alkali metal s.
Elements in group 2 are called alkaline earth metals .
Elements in group 17 are called halogens .
Group 18 element are called inert gasses or noble gases.
Significance of group in the periodic table is that an element in a group has same number of valance electron ,valency and thus identical chemical properties .
1ST PERIOD – 2 elments and is called very short period .
2nd PERIOD- 8 elements and are called short period .
3rd PERIOD – 8 elements and are called short period .
4th PERIOD – 18 elements and are called long period .
5th PERIOD – 18 elements and are called long period .
6th PERIOD – 32 elements and are called very long period .
7th PERIOD- incomplete period .
The number of shell present in the element indicates the period to which it belongs .
It is defined as the combing capacity of an atom of an element to acquire noble gas configuration. it is equal to the number of electron lost , gained or shared during the formation of chemical compound .
ATOMIC SIZE / ATOMIC RADII:
It is defined as the distance from the centre of the nucleus to the outer most cell of atom . it is generally expressed in pico meter ( pm) .
On moving down the group the atomic radii increases.
Because on moving down the group a new energy shell is added which increases the distance between the outermost electron and the nucleus . All though the nucleus charge also increases , but it is compensated by the additional shell being added thus , increasing the size of the atom .
Across the period the atomic radii decrease. Due to the increase nuclear charge , the pull on the electron increases and hence, they are pulled closer to the nucleus thus, decreasing the atomic size .
Oxides and its nature. Metal reacts with oxygen to form oxides by loss of electrons. These oxides on dissolution in water from bases.
REACTIVITY OF ELEMENTS.
Down the group reactivity of metal increases as the tendency to lose electron increases due to the increased atomic size .
Reactivity of non metals decreases down the group because of the increased atomic size and the tendency to gain electron decreases.
On moving across the period the reactivity first increases due to the decreased in the metallic character and increase in nonmetallic character.
FORMATIVE ASSESSMENT III
TIME: 1 HRS
Q.1what is the position of hydrogen in the modern periodic table? (1)
Q.2 where are the isotopes of the same elements having different atomic masses placed in the periodic table ? (1)
Q.3 An element M is the third group of the periodic table. Write the formula of its oxide? (1)
Q.4 What is the valency of magnesium with atomic no. 12 and chlorine with atomic no. 17? (1)`
Q.5what is the difference in number of shell in magnesium and sulphur? (1)
Q.6 on the basis of electronic configuration , how will you select (1)
i)the terminating member in a period .
ii) the chemically similar elements .
Q.7Give reason as to why the atomic radii of elements increase in a group while moving from top to bottom ? (2)
Q.8 element in a group of periodic table have similar chemical properties why ? (2)
Q.9 explain why atomic number is more important than atomic weight in determining chemical properties ? (2)
Q. 10 where in periodic table do we find :
i)elements classified as non metal .
ii) elements forming negative ions .
iii)elements with high melting points .
iv)elements forming positive ions . (2)
Q.11 in a group reactivity of metals increases while those of non metals decreases . Explain. (2)
Q.12 elements in a group of periodic table have similar chemical properties why (2)
Q.13 elements of group 18 are called zero group. Why? (2)
Q.14 write the electronic configuration of atoms of
A)potassium (K) B)argon (Ar) C)lithium (li) D)fluorine (F) E)chlorine (Cl) (5)
Q.15i)Why is potassium more reactive than lithium ?
ii)why is fluorine is more reactive than chlorine ?
iii)which is smaller in size Cl or Ar ?
iv)which is smaller in size Li or F ?
v)which is more electronegative F or Cl?
Q.16The atomic no. of an element is 17.
i)what is its valency?
ii) Whether it is a metal or non-metal?
iii) Whether it is bigger or smaller in size then an element of atomic no.18?
iv) What type of bonds it will form with elements of group 18?
v) How would its oxide behave with litmus solution? (5)