1. Sr.No.
Index
1.
The Year Plan
2.
Selection Of The Sub-Units
3.
The Unit Plan
4.
The Lesson Plan
5.
Weightage Table
6.
The Blue-Print
7.
The Question Bank
8.
Selection Of The Test Item
9.
Grouping Of The Test Item
10.
Scheme Of Option
11.
Instruction To The Examinees.
12.
The Scoring Key
13.
The Marking Scheme
14.
The Unit Test Paper
15.
Critical Evaluation By The Expert
16.
Analysis And Interpretation Of The Results.
Calculation Of The Mean
Calculation Of The S.D.
17.
Graphical Interpretation Of The Scores
Histogram
The Frequency Polygon
1
Page No.
2. The Year Plan
Number of periods available per week =6
Number of days in a year =365
Number of days not available for teaching =220
Number of days available for teaching
= Number of days in a year – Number of Holidays
=365-220
=145
Number of weeks available for teaching
= Number of days available for teaching/5
=145/5
=29
Number of periods available for teaching
=Number of weeks*Number of period per week
=29*6
=174 periods
Total number of periods used
=Number of teaching period + Number of testing period
=128+46
=174 periods
2
3. 2.Water-A natural resource.
3.Properties of Water.
Unit-II
4.Propogation of Light.
Unit-III
5.Electric Charge.
6.Transmission of Heat
7.Effects of Heat
Unit-V
8.Sound-Production of Sound.
9.Propogation of Sound.
Unit-VI
10.Food & Nutrition.
11.Food & Production of Food.
12.Health & Disease.
Unit-VII
13.The Organization of Living
Things.
14.Reproduction of Living
Things.
15.Circulation of Blood.
16.Control & Co-ordination
Teaching
Periods
Testing
Periods
TOTAL
APPRECIATION
ATTITUDE
INTEREST
UNDERSTANDI
NG
APPLICATION
1.Natural Resources.
SKILL
KNOWLEDGE
Name of the Topics
Unit-I
7
3
10
5
1
6
6
2
8
7
3
10
9
3
12
7
9
3
3
10
12
8
3
11
8
3
11
9
3
12
9
6
3
2
12
8
6
2
3
5
2
7
8
9
3
3
11
12
7
3
10
3
128
1
46
4
174
Unit-IV
Unit-VIII
17.Classification of Substances.
Unit-IX
18.Acids,Bases and Salts.
TOTAL
3
4. SELECTION OF THE SUB-UNITS
Subject: Science
Topic: Acids,Bases and Salts
Std.: VII
SUB-UNIT- 1
First Property of Acid & Bases
Concept & Definitions of Indicators.
Litmus Test Activity.
Second Property of Acid & Bases.
Definition of Neutral substances
SUB-UNIT- 2
Test of Oxides of Metals(Basic)
Test of Oxides of Non-metals(Acidic)
Definitions of Neutralization.
SUB-UNIT- 3
Classification of Salts.
Use of Acids & Bases.
4
5. THE UNIT PLAN
Content
Analysis
Learning Experience,Learning Evaluation
Situations,Learning Activity
Sub-Unit-I
(First property of Acids and Bases, Indicators, Litmus Test Activity, Second property of Acids
and Bases, Neutral Substances.)
Stage-I
1.First property Knowledge:1.The pupil recalls
The
teacher
of Acids &
that lemon juice is sour to describes the first property of
Bases.
taste.
acids and bases by showing
2.The pupil recognizes that some known substances such as
sour to
sour substances are acids & lemon ,lime ,soap and vinegar
taste
Astringe astringent substances are bases. as acids are sour to taste and
Understanding:
1.The pupil bases are astringent to taste.
nt taste
discriminates between acid & She explains ,it is wrong to
2. Indicators.
bases.
taste or touch substances to find
Natural
Chemica Application:1.The pupil cites whether the substance is an
examples of more substances acid or a base. Then, she
l
which are sour to taste.
introduces substances like
Skill:1.Thepupil
records litmus,turmeric
observations accurately.
,phenolphthalein and methyl
orange as those substances
which help us to identify an
acid or a base, tems them as
indicators and classifies them
as natural and chemical
indicators.
1.Litmus Test
Activity.
2.Second
property of
Acids & Bases.
Turns
blue
litmus
red(acid)
.
Turns
red
litmus
blue(bas
e).
3.Neutral
Substances.
Objectives(with
Specifications.)
Stage-II
Knowledge:1.The pupil recalls
The teacher performs the
that indicators are used to litmus test activity on different
identify given substances.
substances such as hydrochloric
2.The pupil recognizes that acid, sulphuric acid ,sodium
indicators are of two types.
hydroxide ,lime solution and
Understanding:
1.The pupil she concludes that acid turns
discriminates between acid , blue litmus paper red while red
bases and neutral substances.
litmus remains unchanged ,
Application:1.The pupil gives bases turns red litmus paper
reason for change in colour of blue while blue litmus remains
litmus paper when dipped on unchanged and the substance
different solutions.
which has no effect on red or
Skill:1.Thepupil
records blue litmus paper are called as
observations of litmus test neutral substances.
activity accurately.
5
6. Content Analysis
Objectives(with Specifications.)
Learning
Evaluation
Experience,Learning
Situations,Learning
Activity
Sub-Unit-II
(Simulation of Oxides of metals , Oxides of non-metals
And demonstration of Neutralization.)
Stage –I
The teacher
Oxides of metals. Knowledge:1.The pupil recalls
that elements are classified into stimulates the
Oxides of nonmetals and non-metals.
experiment of
metals
2.The pupil recognizes that formation of
oxides
are
formed
by sulphurous acid and
combination of oxygen with any simultaneously she
substance.
writes the chemical
Understanding:
1.The pupil reactions on the
discriminates between oxides of B.B.:
metals and non-metals.2.The S
+ O2
pupil generalizes that oxides of SO2
metals are basic and oxides of SO2 + H2O
non-metals are acidic in nature. H2SO3
Application:1.The
pupil
analyzes that SO2 is formed by and does the litmus
burning of sulphur.2.The pupil test activity
predicts the nature of the newly similarly she
formed chemical substance.
stimulates the
Skill:1.The
pupil
records formation of
observations accurately.
magnesium
hydroxide and
simultaneously she
writes the chemical
reactions on the
B.B.:
2Mg + O2
2MgO
2MgO + H2O
Mg(OH)2
and does the litmus
test activity
Demonstration of
Neutralization
reaction.
Definition
Chemical
Reaction
Stage –II
(Neutralization reaction)
Knowledge:1.The pupil recalls
that .acids and bases have
equally opposite properties
2.The pupil recognizes that salt
and water are formed as a
chemical reaction between acids
6
The
teacher
demonstrates
the
neutralization
reaction as follows:
She takes NaOH in
one test-tube and
7. and bases .
Understanding:
1.The pupil
discriminates between acids,
bases and salts.2.The pupil sees
a
relationship
between
acid,bases
and
salts
in
neutralization reaction.
Application:1.The
pupil
predicts the new product in a
neutralization reaction.
Skill:1.The
pupil
records
observations of the chemical
reaction accurately.
7
puts a drop of
phenolphthalein in it
and
asks
the
students to observe
the
change
in
colour. she takes
HCl in other testtube and puts a drop
of phenolphthalein
in it and asks the
students to observe
the
change
in
colour. Then, she
pours NaOH into
HCl and puts a drop
of phenolphthalein
in it and asks the
students to observe
the
change
in
colour.
8. Content Analysis
Classification of
Salts
Neutral salts
Acidic salts
Basic salts
Uses of Acids and
Bases:
Acids:
1.Citric Acid.
2.Tartaric Acid.
3.Lactic Acid.
4.Benzoic Acid
5.Acetic Acid.
6.Hydrochloric
Acid.
Bases:
1.Magnesium
hydroxide
2.Quicl lime.
Objectives(with
Specifications.)
Learning
Experience,Learning
Situations,Learning Activity
Sub-Unit-III
(Classification of Salts and Uses of Acids and Bases.)
Stage –I
(Classification of Salts)
Knowledge:1.The
pupil
The teacher Classifies the
recalls
salts into Neutral ,Acidic
2.The pupil recognizes that and Basic .Then she gives
Understanding:
1.The some examples of each of
pupil discriminates between the different types of salts.
Application:1.The
pupil
Skill:1.The pupil records
observations accurately.
Stage –II
(Uses of Acids and Bases )
Knowledge:1.The
pupil The teacher explains the
recalls that . 2.The pupil different uses of acids and
recognizes that
bases in everyday life. She
Understanding:
1.The describes that some acids
pupil discriminates between make our food tasty.some
Application:1.The
pupil are used as preservatives.
formulates a hypothesis that Some are used as
an acid can be neutralized disinfectant. Even bases are
by a base.
used in medicines.
Skill:1.The pupil records
observations
of
the
chemical
reaction
accurately.
8
Evaluation
9. WEIGHTAGE TABLES
WEIGHTAGE OF THE OBJECTIVES:Knowledge
Understanding
Application
Skill
Total
20
40
20
20
100
Marks
4
8
4
4
20
WEIGHTAGE OF THE AREA OF CONTENT:Sub-unit-1
Sub-unit-1
Sub-unit-1
Total
35
40
25
100
Marks
7
8
5
20
WEIGHTAGE TO DIFFICULTY LEVEL:Easy
Average
Difficult
Total
30
40
30
100
Marks
6
8
6
20
WEIGHTAGE OF THE FORMAT OF QUESTIONS:Essay
Short-answer
Objective
Total
30
50
20
100
Marks
6
10
4
20
9
11. THE QUESTION BANK
SUB-UNIT-1
Sr.
no.
I.
II.
III.
IV.
V.
VI.
Questions
Fill in the blanks:
1……. do not shows the
properties of either acids
or bases.
2……..is obtained from
plants called lichens.
3.Acids and bases have
mutually
……….properties.
4.Acids turns
………litmus red.
5.Bases turns …….litmus
blue.
Match the following:1.Acids –Sour to taste.
2.Bases – Astringent taste.
3.Litmus – Indicator.
4.Water – Neutral.
Objectives
Specifications
Form
Marks
Time
Knowledge
Recalls
Objective
01
½
Knowledge
Recalls
Objective
01
½
Knowledge
Recalls
Objective
01
½
Knowledge
Recalls
Objective
01
½
Knowledge
Recalls
Objective
01
½
Knowledge
Knowledge
Knowledge
Knowledge
Recognizes
Recognizes
Recognizes
Recognizes
Objective
Objective
Objective
Objective
01
01
01
01
½
½
½
½
Recalls
Objective
01
½
Recalls
Objective
01
½
Recalls
Objective
01
½
Compare
Objective
02
1
Compare
Compare
Objective
Objective
01
01
½
½
Recalls
Objective
01
½
Recalls
Objective
01
½
State True or False;1.Neutral substances
shows the properties of
Knowledge
both acids and bases.
2.Acids turns blue litmus
Knowledge
paper red.
3.Bases turns red litmus
Knowledge
paper blue.
Classify the following
into acids,bases and
Understanding
neutral:
HCl,H2SO4,NaOH,CaCO3
,H2O,NaCl
Find the odd man out:1.HCl,H2SO4,HNO3,NaCl Understanding
2.Ca2(OH),NaOH,NH4OH Understanding
,CH3COOH
Name the following:1.Natural indicator to
Knowledge
detect acid or base.
2.Plant from where litmus
Knowledge
is obtained.
11
12. 3.Substances which do not
affect indicators.
Give Scientific reasons:1.Tamarind makes our
teeth go on edge when we
eat it.
2.Blue litmus turns red
when added to lemon
juice.
Define giving example:1.Indicators
2. Neutral substances
VII.
VIII.
IX.
State the effect of red
litmus & blue litmus
paper on
HC1,H2SO4,Ca(OH)2
,NaOH,NaCl
X.
Write a short note:1.Indicators.
2.Effect of Litmus and
Phelophthalein on acids
and bases.
Sr.no.
I.
II.
III.
Knowledge
Recalls
Objective
Application
Give reasons
Short
Answer
02
Application
Give reasons
Short
Answer
02
3
02
02
3
3
Short
Answer
02
3
Knowledge
Knowledge
Recalls
Recalls
01
Short
Answer
Short
Answer
½
3
Understanding
Recalls
Understanding
Explains
Essay
03
5
Understanding
Explains
Essay
03
5
Questions
Fill in the blanks:1.The main constituent of
an acid is……….
2. The main constituent
of an base is……….
3.The Chemical reaction
that takes place between
an acid and a base is
called ……….
4.Bases that dissolve in
water are called ……….
Match the following:1.Oxides of metal –
Bases
2.Oxides of non-metal –
Acids
3.Sulphur – Non-Metal
4.Magnesium –Metal
State whether true/false:1.Oxides of metals are
acidic.
SUB-UNIT-2
Objectives
Specifications
Form
Marks
Time
01
½
Knowledge
Recalls
Objective
Knowledge
Recalls
Objective
01
½
Knowledge
Recalls
Objective
01
½
Knowledge
Recalls
Objective
01
½
Knowledge
Knowledge
Recognizes
Recognizes
Objective
Objective
01
01
½
½
Knowledge
Knowledge
Recognizes
Recognizes
Objective
Objective
01
01
½
½
Objective
01
½
Knowledge
Recalls
12
13. IV.
V.
VI.
VII.
VIII.
2.Common salt is acidic.
3.Bases are formed by
neutralization reaction
between acids and salts.
Find the co-orelation:1.Oxides of
metal:Basic::Oxides of
non-metal:………
2.Acid:H::Base:…….
Find the odd man out:1.MgO,CaO,H2O,Na2O.
2.NaCl,C12H12O11,KCl,C
uSO4.
3.NaHCO3,NaOH,NH4O
H,CH3COOH.
4.HCl,H2SO4,HNO3,NaC
l.
Classify the following
into acidic,basic and
neutral:HCl,NaCl,MgO,KCl,Ca
O, H2SO4,HNO3,
H2O,Na2CO3
Name the following:1.Chemical formed when
an element combines
with a oxygen.
2.Acid formed when
sulphur dioxide dissolves
in water.
3.Base formed when
magnesium oxide
dissolves in water.
4.Bases that dissolves in
water.
Give Scientific reasons:1.Pheolphthalein solution
turns to pink when added
to a solution of
magnesium hydroxide or
lime solution.
2.Hydroxides of copper
have to be prepared by
chemical reactions and
not by dissolving an
oxide.
OR
2.Copper hydroxide is
basic but not aan alkali in
water.
Knowledge
Recalls
Objective
01
½
Knowledge
Recalls
Objective
01
½
Understanding
Compare
Objective
01
½
Understanding
Compare
Objective
01
½
Understanding
Understanding
Compares
Compares
Objective
Objective
01
01
½
½
Understanding
Compares
Objective
01
½
Compares
Objective
01
½
Understanding
Understanding
Compares
Compares
Objective
Objective
01
01
½
½
Knowledge
Recalls
Objective
Knowledge
Recalls
Objective
Understanding
01
½
½
01
½
Knowledge
Recalls
Objective
01
½
Knowledge
Recalls
Objective
01
½
Application
Give reasons
Short
Answer
02
3
Application
Give reasons
Short
Answer
02
3
13
14. IX.
Distinguish between:1.Acids and Bases.
2.Base and Alkali.
Define giving examples:1.Neutralization.
2.Alkali.
Explain what happens:
Or Give chemical
reaction:-
Short
Answer
02
02
3
3
Recalls
Recalls
Short
Answer
02
02
3
3
Skill
Describes/
Explains
Short
Answer
02
½
Skill
Describes/
Explains
Describes/
Explains
Describes/
Explains
Short
Answer
Short
Answer
Short
Answer
02
½
02
½
02
½
Understanding
Describes/
Explains
Essay
03
5
Understanding
Describes/
Explains
Essay
03
5
3.Explain the formation
of Magnesium
hydroxide.
XI.
Differentiates
Differentiates
2.Explain the formation
of Sulphurous acid.
X.
Understanding
Describes/
Explains
Essay
03
5
Describe an experiment
to show an acid can be
neutralized by base.
Knowledge/
Understanding
Recalls/
Describes/
Explains
1.Hydrochloric acid
reacts with ammonium
hydroxide.
2.Sulphur dioxide reacts
with water.
3.Magnesium reacts with
oxygen.
4.Sulphur reacts with
oxygen.
XII.
XIII.
Answer briefly:1.Short note on
Neutralization.
Understanding
Understanding
Knowledge
Knowledge
Skill
Skill
14
Essay
03
5
15. SUB-UNIT-3
Sr.
no.
I.
II.
III.
Questions
Fill in the blanks:1.Tartaric acid is
a………acid.
2. Acetic acid and
benzoic acid are used
for preserving ………..
and …………
3.To get acidic
salts………..acids are
used.
4.There is a………..acid
in our stomach.
Match the following:1.Tamarind – Tartaric
acid.
2.Yoghurt –Lactic acid.
3.Lemon – Citric acid.
4.Vinegar –Acetic acid.
State whether true or
false:1.To get acidic
salts,,weak acid is used.
2. To get basic
salts,strong acid is used .
3. To get neutral
salts,strong acid and a
weak base is used.
Objectives
Specifications
Form
Marks
Time
Knowledge
Recalls
Objective
01
½
Knowledge
Recalls
Objective
01
½
Knowledge
Recalls
Objective
01
½
Knowledge
Recalls
Objective
01
½
Knowledge
Recognizes
Objective
01
½
Knowledge
Knowledge
Knowledge
Recognizes
Recognizes
Recognizes
Objective
Objective
Objective
01
01
01
½
½
½
Knowledge
Recalls
Objective
01
Knowledge
Recalls
Objective
01
½
Knowledge
Recalls
Objective
01
½
Knowledge
Knowledge
Knowledge
Knowledge
Recognizes
Recognizes
Recognizes
Recognizes
Objective
Objective
Objective
Objective
01
01
01
01
½
½
½
½
Knowledge
Knowledge
Recognizes
Recognizes
Objective
Objective
01
01
½
½
Knowledge
Recognizes
Objective
01
½
Application
Give reasons
Short
Answer
02
½
IV.
V.
Name the following:1.Acidic salt.
2.Basic salt.
3.Neutral salt.
4.Vitamin present in
Citrus fruit.
5.Acid in tamarind.
6.Substances added to
acidic soil to increase
fertility.
7.Substances added to
make alkaline soil
fertile.
Give Scientific reasons:1.Medicine containing
magnesium hydroxide is
15
3
16. given to a patient
suffering from stomach
ache caused due to
acidity.
2.Quick lime or slaked
lime is sometimes added
to soil.
VI. Write a short note on:1.Different types of
salts.
2.Uses of acids and
bases
VII. Answer briefly:1.Statues of marble get
spoiled when exposed to
vehicular pollution.
Application
Give reasons
Short
Answer
02
Understanding
Understanding
Explains
Explains
Essay
Essay
03
03
5
5
Understanding
Explains
Essay
03
5
16
3
17. SELECTION OF TEST-ITEMS
SUB-UNIT-1
Sr.
no.
I.
II.
III.
IV.
Questions
Fill in the blanks:
1.……..is obtained from
plants called lichens
State True or False;1.Neutral substances shows
the properties of both acids
and bases.
Give Scientific reasons:1.Tamarind makes our teeth
go on edge when we eat it.
Write a short note:1.Indicators.
Objectives
Specifications
Form
Marks
Time
Knowledge
Recalls
Objective
01
½
Knowledge
Recognizes
Objective
01
½
Application
Give Reasons
Short
Answer
02
3
Understanding
Describes
Essay
03
3
SUB-UNIT-2
Sr.
Questions
no.
I. Fill in the blanks:1.Bases that dissolve in
water are called ……….
Specifications
Form
Marks
Time
Knowledge
Recalls
Objective
01
½
Knowledge
Recognizes
Objective
01
½
Understanding
Compares
Objective
½
½
2.NaCl,C12H12O11,KCl,CuSO. Understanding
II.
Objectives
Compares
Objective
½
Compares
Objective
½
½
]
½
Compares
Objective
½
½
State whether true or
false:1.Oxides of metals are
acidic.
III. Find the odd man out:1.MgO,CaO,H2O,Na2O.
3.NaHCO3,NaOH,NH4OH
,CH3COOH.
Understanding
4.HCl,H2SO4,HNO3,NaCl.
Understanding
IV. Explain what happens:
Or Give chemical
17
18. reaction:1.Hydrochloric acid reacts
with ammonium
hydroxide.
Skill
V.
Give Scientific reasons:1.Pheolphthalein solution
turns to pink when added
to a solution of magnesium
hydroxide or lime solution.
02
3
Describes
3
Describes
Short
Answer
Short
Answer
02
Skill
3.Magnesium reacts with
oxygen.
Short
Answer
Skill
2.Sulphur dioxide reacts
with water.
Describes
02
3
Short
Answer
02
3
Application
Give reasons
SUB-UNIT-3
Sr.
no.
I.
II.
Questions
Objectives
Specifications
Form
Marks
Time
Give Scientific reasons:1.Quick lime or slaked lime is
sometimes added to soil.
Application
Give Reasons
Short
Answer
02
3
Understanding
Understanding
Describes
Describes
Essay
Essay
03
03
5
5
Write a short note on:1.Different types of salts.
2.Uses of acids and bases.
18
19. GROUPING OF TEST-ITEMS
Grouping
I
II
III
IV
V
VI
Questions
Fill in the blanks:1.……..is obtained from
plants called lichens.
2.Bases that dissolve in
water are called ……….
Find the odd man out:1.MgO,CaO,H2O,Na2O.
2.NaCl,C12H12O11,KCl,C
uSO4.
3.NaHCO3,NaOH,NH4O
H,CH3COOH.
4.HCl,H2SO4,HNO3,NaCl
.
State True or False;1.Neutral substances
shows the properties of
both acids and bases.
2.Oxides of metals are
acidic.
Explain what happens:
Or Give chemical
reaction:1.Hydrochloric acid
reacts with ammonium
hydroxide.
2.Sulphur dioxide reacts
with water.
3.Magnesium reacts with
oxygen.
Give Scientific reasons:1.Tamarind makes our
teeth go on edge when we
eat it.
2.Pheolphthalein solution
turns to pink when added
to a solution of
magnesium hydroxide or
lime solution.
3. Quick lime or slaked
lime is sometimes added
to soil.
Write a short note:1.Indicators.
2.Different types of salts.
3.Uses of acids and bases
Objectives
Specifications
Form
Marks
Time
Knowledge
Recalls
Objective
01
½
Knowledge
Recalls
Objective
01
½
Understanding
Understanding
Understanding
Compares
Compares
Compares
Objective
Objective
Objective
½
½
½
½
½
½
Compares
Objective
½
½
Knowledge
Recognizes
Objective
01
½
Knowledge
Recognizes
Objective
01
½
Skill
Describes/
Explains
Describes/
Explains
Describes/
Explains
Short
Answer
Short
Answer
Short
Answer
02
3
02
3
02
3
Application
Give reasons
02
3
Application
Give reasons
Short
Answer
Short
Answer
02
3
Application
Give reasons
Short
Answer
02
3
Understanding
Understanding
Understanding
Describes
Describes
Describes
Essay
Essay
Essay
03
03
03
5
5
5
Understanding
Skill
Skill
19
20. SCHEME OF OPTION
IV. Explain what happens when OR Give chemical reactions and balance it :(any 2 out of 3)
V. Give Scientific reasons :(any 2 out of 3)
VI. Write a short note on :(any 2 out of 3)
20
21. INSRTUCTION TO THE EXAMINEES
The following general instructions were given to the examinees at the beginning of the
question paper.
a)
b)
c)
d)
e)
Questions I,II & III are compulsory.
Questions IV,V & VI have internal options.
Read each question carefully.
Figure to the right indicates maximum number of marks obtainable in each question.
The total number of marks carried is 20.
THE SCORING KEY
Objective Type Questions:- I.Fill in the Blanks
II.State whether True or False
III.Find the Odd man out
Sr.No.
Expected Answer:-
Marks
Special Instructions
I.
1.
2.
Fill in the Blanks
Litmus
Alkali
1
1
Nil
Nil
II.
1.
2.
3.
4.
Find the Odd man out:H2O
C12H12O11
CH3COOH
NaCl
½
½
½
½
Nil
Nil
Nil
Nil
III.
1.
2.
State whether True or False:False
False
1
1
Nil
Nil
21
22. THE MARKING SCHEME
Short Answer/Essay Type Answer:-IV.Give Chemical Reactions
V.Give Scientific Reasons
VI.Write Short Note on
Sr.No.
Expected Answer:-
Marks
IV.
1.
Explain What happens/Give Chemical reactions
When hydrochloric acid reacts with ammonium 2
hydroxide,then ammonium chloride and water
are formed.
2.
When sulphur dioxide reacts with water then
sulphurous acid is formed.
2
Nil
3.
When magnesium reacts with oxygen then
magnesium oxide is formed
2
Nil
V.
1.
Give Scientific reasons
1.Tamarind has tartaric acid.
2.The sour taste of acid is very strong.
Hence,tamarind makes our teeth to go on edge
when we eat it.
2
Nil
2.
1. Phenolphthalein is an indicator which
changes colour in acids andbases.
2.In acid it is colourless and in a base it is pink.
3. Magnesium hydroxide solution is a base
prepared from oxide of a magmesium metal.
4.Lime solution is a base prepared from oxide
of a calcium metal.
Hence,phenolphthalein solutions turns to pink
when added to a solution of magnesium
hydroxide or lime solution.
2
Nil
3.
1.Overuse of chemical fertilizers makes the soil
acidic.
2. Quick lime is basic in nature.Hence,quick
lime is sometimes added to the soil.
2
Nil
22
Special Instructions
Nil
23. VI.
1.
Write short note on
1.Indicators:
Ans:a.Certain substances are used to find
whether the given substance is acid or a
base.such substances are called indicators.
b.When an indicator is added to an acidic or a
basic solution it changes colour.
c.Litmus and turmeric are examples of natural
indicators.
d.Phenolphathalein and methyl orange are
examples of chemical indicators.
3
Nil
2.
3.Types of Salts
3
Ans:Salts are formed when an acid reacts with a
base.Salts are of 3 types:
a.Neutral Salts:They are formed as a result of
chemical reaction between a strong acid and a
strong base.
e.g. NaCl (sodium chloride),etc.
b.Acidic salts: They are formed as a result of
chemical reaction between a strong acid and a
weak base.
e.g. NH4Cl (ammonium chloride),etc.
c.Basic Salts:- They are formed as a result of
chemical reaction between a weak acid and a
strong base.
e.g. Washing soda,Baking soda.etc
Nil
3.
4.Use of acids and bases
a.Citric acid is found in natural foods such as
lemons,oranges,sweetlimes.we get Vitamin C
from these fruits.
b.Tartaric acid in tamarind and lactic Acid in
yoghurt make our food tastier.
c.hydrochloric acid is used for cleaning toilets.
d.Acetic acid,benzoic acid is used in food
preservation.
e. magnesium hydroxide is used in medicines
for neutralizing extra acid in the stomach.
f.Quick lime/Slaked lime is added to acidic soil
to neutralize the acid in the soil.
3
Nil
23
24. THE UNIT-TEST PAPER
St. Paul High School ,Dadar
SUB: Science
Std: VII
Date: 10.02.2014
Marks: 20
Time: 30 min
General Instructions:a) Questions I , II & III are compulsory.
b) Questions IV ,V & VI have internal options.
c) Read each question carefully.
d) Figure to the right indicates maximum number of marks obtainable in each question.
e) The total number of marks carried is 20.
I.Fill in the blanks:1………is obtained from the plant lichens.
2. Bases that dissolves in water are called ………..
2
II.Find the odd man out:1.MgO,CaO,H2O,Na2O.
2.NaCl,C12H12O11,KCl,CuSO4.
3.NaHCO3,NaOH,NH4OH,CH3COOH.
4.HCl,H2SO4,HNO3,NaCl.
2
III.State Whether True or False:1.Oxides of metals are acidic.
2.Neutral Substances shows the properties of both acids and salts.
2
IV.Explain what happens when OR Give chemical reactions and balance it :-(any 2) 4
1.Hydrochloric acid reacts with ammonium hydroxide.
2.Sulphur dioxide reacts with water.
3.Magnesium reacts with Oxygen.
V.Give Scientific reasons :-(any 2)
4
1.Tamarind makes our teeth go on edge when we eat it.
2.Phenolphathalein solution turns to pink when added to a solution of magnesium hydroxide
or
lime solution.
3.Quick lime or Slaked lime is sometimes added to soil.
VI.Write a short note on :-(any 2)
1.Indicators.
2.Use of Acids and Bases.
3.Different Types of Salts.
6
24
25. Critical Evaluation by the Expert
This project in Education Evaluation has been evaluated by professor
Mrs. Sheela Philip who is my method expert.
Thank you mam for guiding me throughout this year.
25
26. Notes given to the students
1.Fill in the blanks:1.The main constituent of an acid is H .
2.The main constituent of a base is OH .
3.Tartaric acid is a organic acid.
4.To get acidic salts strong acids are used.
5.Litmus is obtained from plants called lichens.
6. Bases that dissolves in water are called alkalis.
2.Odd man out:1.MgO,CaO,H2O,Na2O.
Ans:- H2O (neutral)
2.NaCl,C12H12O11,KCl,CuSO4.
Ans:- C12H12O11(sugar)
3.NaHCO3,NaOH,NH4OH,CH3COOH.
Ans:- CH3COOH (acid)
4.HCl,H2SO4,HNO3,NaCl.
Ans:- NaCl (salt)
5. HCl,H2SO4,HNO3,CH3COOH
Ans:- CH3COOH(weak acid)
3.True or False:1.Oxides of metals are acidic .
Ans:-False
2.Neutral Substances shows the properties of both acids and salts.
Ans:-False
3.Common salt is acidic.
Ans:-False
4.Salt is neutral.
Ans:-True
5.Salts are formed by neutralization reaction between acids and bases.
Ans:-True
4.Chemical reactions:
1.Sulphur reacts with oxygen.
Ans:When Sulphur reacts with oxygen,then Sulphur dioxide is formed.
S + O2
SO2
2.Hydrochloric acid reacts with ammonium hydroxide.
Ans:-When hydrochloric acid reacts with ammonium hydroxide,then ammonium chloride and
water is formed.
HCl + NH4OH
NH4Cl + H2O
3.Sulphur dioxide reacts with water.
26
27. Ans:-When Sulphur dioxide reacts with water,then Sulphurous acid is formed.
SO2 + H2O
H2SO3
4.Magnesium Oxide reacts with water.
Ans:- When magnesium oxide reacts with water,then magnesium hydroxide is formed.
2MgO + H2O
Mg(OH)2
5. Magnesium reacts with oxygen.
Ans:-When magnesium reacts with oxygen,then magnesium oxide is formed.
2Mg + O2
2MgO
5.Give scientific reasons:1.Tamarind makes our teeth go on edge when we eat it.
Ans:- a.Tamarind has tartaric acid.
b.The sour taste of acid is very strong. Hence,tamarind makes our teeth go on edge
when we eat it.
2.Blue litmus turns red when added to lemon juice.
Ans:-a. Litmus is an indicator which changes colour in acids andbases.
.b.In acid it is red and in a base it is blue.
.c.Lemon juice contains citric acid. Hence, blue litmus turns red when added to lemon juice.
3.Phenolphthalein solutions turns to pink when added to a solution of magnesium
hydroxide or lime solution.
Ans:-a. Phenolphthalein is an indicator which changes colour in acids andbases.
b.In acid it is colourless and in a base it is pink.
c. Magnesium hydroxide solution is a base prepared from oxide of a magmesium metal.
d.Lime solution is a base prepared from oxide of a calcium metal.
Hence,phenolphthalein solutions turns to pink when added to a solution of magnesium
hydroxide or lime solution.
4.Butter milk kept in copper vessel gets spoiled.
Ans:- a.Butter milk has lactic acid.
b.Copper is a metal, which reacts with lactic acid.Hence, Butter milk kept in copper vessel
gets spoiled.
5.Quick lime is sometimes added to the soil.
Ans:-a.Overuse of chemical fertilizers makes the soil acidic.
b. Quick lime is basic in nature.Hence,quick lime is sometimes added to the soil.
5.Short notes:
1.Indicators:
Ans:a.Certain substances are used to find whether the given substance is acid or a base.such
substances are called indicators.
b.When an indicator is added to an acidic or a basic solution it changes colour.
27
28. c.Litmus and turmeric are examples of natural indicators.
d.Phenolphathalein and methyl orange are examples of chemical indicators.
2.Neutralization
Ans:-a.The Chemical reaction that takes place between acid and bases is called as
Neutralization.
b.It results in the formation of salts and water.
c. When hydrochloric acid reacts with ammonium hydroxide,then ammonium chloride and
water is formed.
HCl + NH4OH
NH4Cl + H2O
3.Types of Salts
Ans:Salts are formed when an acid reacts with a base.Salts are of 3 types:
a.Neutral Salts:They are formed as a result of chemical reaction between a strong acid and a
strong base.
e.g. NaCl (sodium chloride),etc.
b.Acidic salts: They are formed as a result of chemical reaction between a strong acid and a
weak base.
e.g. NH4Cl (ammonium chloride),etc.
c.Basic Salts:- They are formed as a result of chemical reaction between a weak acid and a
strong base.
e.g. Washing soda,Baking soda.etc
4.Use of acids and bases
a.Citric acid is found in natural foods such as lemons,oranges,sweetlimes.we get Vitamin C
from these fruits.
b.Tartaric acid in tamarind and lactic Acid in yoghurt make our food tastier.
c.hydrochloric acid is used for cleaning toilets.
d.Acetic acid,benzoic acid is used in food preservation.
e. magnesium hydroxide is used in medicines for neutralizing extra acid in the stomach.
f.Quick lime/Slaked lime is added to acidic soil to neutralize the acid in the soil.
28
29. ANALYSIS AND INTERPRETATION OF THE
RESULTS
1.Calculation of Mean
Class Interval
0-2
3-5
6-8
9-11
12-14
15-17
18-20
Mean
Mean
Frequency
0
4
19
10
17
10
7
N=67
x
1
4
7
10
13
16
19
x'
-6
-3
0
3
6
9
12
fx'
0
-12
0
30
102
90
84
∑fx'=294
= A.M+ ∑fx'/ N
=7+ 294/67
=7+4.38
=11.38
Interpretation:-It means that the central value of the distribution is 11.38
OR that most of the students in the distribution lie above or below 11.38.Most
of the students have scored around 11.38.
29
30. 2.Calculation of Median
Class Interval
Frequency(f)
F
0-2
0
0
3-5
04
4
6-8
19
23
9-11
10
33
12-14
17
50
15-17
10
60
18-20
7
67
N=67
N/2=33.5
Median = L+ ((N/2 –F)/f *I)
=5.5+(33.5-4/19*3)
=5.5+4.66
Median =10.16
Interpretation:-It is the positional average of the distribution. It divides the
distribution into two equal halves.It implies that 50% of the students lie below
or above 10.16. If N=67,then 33.5 students lie below 10.16 and 33.5 students
lie above it.
30
32. M + 1S.D. =68.26% of cases
M + 2S.D. =95.44% of cases
M + 3S.D. =99.73% of cases
Mean=11.38 and S.D.=4.38
M + 1S.D. =11.38 +4.38=15.76=16
M -1S.D. =11.38 -4.38=7
Thus, Range lies between 7-16.
Therefore Number of cases falling within this range
=8+7+3+6+1+12+3+2+2+2
=46
N= 53
Out of 67………46cases
Out of 100…………. ?
=(100*46)/67
=68.66%
Interpretation:- This means that M + 1S.D. covers 68.66% of the cases.
But according to the formulae, in a normal distribution ,M + 1S.D. covers
68.26% of the cases.
This implies that the given distribution is normal.
32
33. GRAPHICAL INTERPRETATION OF THE
SCORES
1.THE HIISTOGRAM
Class Interval
Frequency
0-2
0
3-5
4
6-8
19
9-11
10
12-14
17
15-17
10
18-20
7
THE HISTOGRAM
19
20
17
18
16
14
12
10
10
10
7
8
6
4
4
2
0
0
0-2
3-5
6-8
9-11
12-14
33
15-17
18-20
Frequency
