TNPSC Chemistry - Acids Bases Salts and Redox Reactions
Exam Duration: 45 Mins Total Questions : 30
Consider the following statements about oxidation
It is the process which involves
1. removal of oxygen
2. addition of hydrogen
3. removal of an electropositive element.
4. addition of an electronegative element.
which of the above is/are false about reduction?
- (a)
Only 1
- (b)
1 and 2
- (c)
3 and 4
- (d)
All of these
A redox reaction is
- (a)
proton transfer reaction
- (b)
ion combination reaction
- (c)
a reaction is solution
- (d)
electron transfer reaction
What is the pH of an aqueous solution having OH- ions concentration equal to 10-2 mol L-1 ?
- (a)
2
- (b)
12
- (c)
10
- (d)
6
Starch iodide paper is used to test for the presence of
- (a)
iodine
- (b)
iodine iron
- (c)
oxidising agent
- (d)
reducing agent
Consider the following statements
It is the process which involves
1. addition of oxygen
2.removal of hydrogen
3. addition of an electronegative element
4. removal of an electropositive element
Which of the above are correct about oxidation?
- (a)
1 and 2
- (b)
2 and 3
- (c)
2, 3 and 4
- (d)
all of these
What is the pH of pure water?
- (a)
1
- (b)
7
- (c)
5
- (d)
12
The pH of fresh ground water slightly decreases upon exposure to air because
- (a)
carbon dioxide from air is dissolved in the water
- (b)
Oxygen from air is dissolved in the water
- (c)
the dissolved carbon dioxide of the ground water escapes into air
- (d)
the dissolved oxygen of the ground water escapes into air
Match Column I with Column II
Column I | Column II |
A. Tartaric acid | 1. Red ants |
B. Formic acid | 2. Grapes |
C. Uric acid | 3. Apples |
D. Maleic acid | 4. Urine of mammals |
- (a)
A B C D 2 1 4 3 - (b)
A B C D 1 4 3 2 - (c)
A B C D 4 3 2 1 - (d)
A B C D 3 2 1 4
Which of the following oxides is a neutral oxide?
- (a)
NO2
- (b)
CO2
- (c)
CaO
- (d)
CO
Carboxylic acid group can be detected by
- (a)
sodium bisulphite test
- (b)
Fehling's solution test
- (c)
Tollen's reagent
- (d)
NaHCO3
Match Column I with Column II
Column I | Column II |
A. NH3 | 1. Lewis base |
B. HCN | 2. Lewis acid |
C. BF3 | 3. Strongest acid |
D. HCIO4 | 4. Weakest acid |
- (a)
A B C D 1 4 2 3 - (b)
A B C D 3 1 4 2 - (c)
A B C D 4 2 3 1 - (d)
A B C D 2 4 1 3
Acid turns blue litmus red and base turns red litmus blue. A student tested liquid with a red litmus paper which remained red with no change. This shows that the liquid
- (a)
is not a base
- (b)
is not an acid
- (c)
is neither an acid nor a base
- (d)
must be a pure water
Which one of the following statements is correct?
- (a)
All bases are alkali
- (b)
None of the bases is alkali
- (c)
There are no more bases except the alkalies
- (d)
All alkalies are bases but all bases are not alkalies
Match Column I with Column II and select the correct answer using the codes given the columns
Column I (Oxidation Number) |
Column II (The Element) |
A. 2 | 1. Oxidation number of Mn in MnO2 |
B. 3 | 2. Oxidation number of S in H2S2O7 |
C. 4 | 3. Oxidation number of Ca in CaO |
D. 6 | 4. Oxidation number of AI in NaAIH4 |
- (a)
A B C D 3 4 1 2 - (b)
A B C D 4 3 1 2 - (c)
A B C D 3 4 2 1 - (d)
A B C D 4 3 2 1
Arrange the following bases in increasing order of their, basic strength.
1. Sodium hydroxide
2. Magnesium hydroxide
3. Aluminium hydroxide
4. Ammonium hydroxide
- (a)
A B C D 4 2 1 3 - (b)
A B C D 4 1 2 3 - (c)
A B C D 4 3 2 1 - (d)
A B C D 1 2 3 4
Why hard water does not give lather with soap?
- (a)
Hard water contains calcium and magnesium ions which form precipitate with soap
- (b)
Hard water contains sulphate and chloride ions which form precipitate
- (c)
pH of hard water is high
- (d)
pH of hard water is less
Statement I Addition of water to an aqueous solution of HCL decreases the pH.
Statement II Addition of water suppresses the ionisation of HCL.
- (a)
Both the statements are individually true and statement II is the correct explanation of statement I
- (b)
Both the statements are individually true but statement II is not the correct explanation of statement I
- (c)
Statement I true but Statement II is false
- (d)
Statement I is false but statement II is true
Match Column I with Column II
Column I | Column II |
A.10-7 | 1. pH value of neutral solution |
B. >7 | 2. pH value of acidic solution |
C. <7 | 3. pH value of alkaline |
D. 7 | 4. In pure water hydrogen ion concentration |
- (a)
A B C D 1 4 3 2 - (b)
A B C D 2 1 4 3 - (c)
A B C D 3 2 1 4 - (d)
A B C D 4 3 2 1
Match Column I with Column II
Column I (pH Value) |
Column II (Product) |
A. 7.35 to 7.45 | 1. Milk |
B. 6.6 | 2. Human blood |
C. 8.5 | 3. Wine |
D. 2.8 | 4. Sea water |
- (a)
A B C D 1 4 3 2 - (b)
A B C D 2 1 4 3 - (c)
A B C D 4 3 2 1 - (d)
A B C D 3 2 1 4
The pH of water at 25\(^{o}\)C is 7. When it is heated to 100\(^{o}\)C, the pH of water
- (a)
increases
- (b)
decreases
- (c)
remains same
- (d)
decreases up to 50\(^{o}\) C and then increases
Iodized salt is a
- (a)
mixture of potassium iodide and common salt
- (b)
mixture of molecular iodide and common salt
- (c)
Compound formed by combination of potassium iodide and common salt
- (d)
compound formed by molecular iodine and common salt
Which of the following gases in the atmosphere is/are responsible for acid rains?
1. Oxides of sulphur
2. Oxides of nitrogen
3. Oxides of carbon
Select the correct answer using the codes given below,
- (a)
1 and 2
- (b)
1 and 3
- (c)
Only 2
- (d)
1, 2 and 3
A base is a substance which
- (a)
is bitter in taste
- (b)
gives OH- ions in aqueous solution
- (c)
can donate electron
- (d)
All of the above
Which of the following salts when dissolved in water makes the solution basic?
- (a)
Sodium chloride
- (b)
Copper sulphate
- (c)
Ferric chloride
- (d)
Sodium acetate
Which one of the following is correct? Due to continuous use of calcium superphosphate as fertilizer in soil, the pH of soil increases or decreases
- (a)
more than 7
- (b)
less than 7
- (c)
equal to 7
- (d)
cannot be predicted
Solution in test tubes containing H2O and aqueous NaOH can be differentiated with the help of
- (a)
red litmus
- (b)
blue litmus
- (c)
Na2CO3
- (d)
HCL(aqueous)
Which one among the following is not a property of salt?
- (a)
salts have ordered packing arrangements called lattices
- (b)
Salts have low melting points but high boiling point
- (c)
Salts are brittle
- (d)
Salts conduct electricity when dissolved in water or even in the Molton state
Consider the following statements
1. Acids are sour in taste and change the colour of blue litmus to red.
2. Bases are bitter and change the colour of red litmus into blue.
3. Litmus is natural indicator.
Which of the statements above are correct?
- (a)
1 and 2
- (b)
1 and 3
- (c)
2 and 3
- (d)
1, 2 and 3
Study the following statements
1. Litmus solution is a purple dye which extracted from lichen and is commonly used as an indicator.
2. Red cabbage leaves, turmeric, coloured petals of some flowers indicate the presence of acid or base in a solution.
3. some substances whose odour changes in acidic or basic medium are called olfactory indicators.
Which of the statements given above are correct?
- (a)
1, 2 and 3
- (b)
1 and 2
- (c)
1 and 3
- (d)
2 and 3
Consider the following statements
1. Limestone, chalk and marble are different forms of calcium carbonate.
2. When PH of rain water is less than 5.6, it is called acid rain.
3. Human body works with in the PH range od 7.0 to 7.8.
Which of the statements given above are correct?
- (a)
1 and 2
- (b)
1 and 3
- (c)
2 and 3
- (d)
1, 2 and 3