Test: Class 10 General Science NCERT Based - 1


15 Questions MCQ Test Science & Technology for UPSC CSE | Test: Class 10 General Science NCERT Based - 1


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This mock test of Test: Class 10 General Science NCERT Based - 1 for UPSC helps you for every UPSC entrance exam. This contains 15 Multiple Choice Questions for UPSC Test: Class 10 General Science NCERT Based - 1 (mcq) to study with solutions a complete question bank. The solved questions answers in this Test: Class 10 General Science NCERT Based - 1 quiz give you a good mix of easy questions and tough questions. UPSC students definitely take this Test: Class 10 General Science NCERT Based - 1 exercise for a better result in the exam. You can find other Test: Class 10 General Science NCERT Based - 1 extra questions, long questions & short questions for UPSC on EduRev as well by searching above.
QUESTION: 1

Regarding the Chemical reactions, consider the following statements:

1. New atoms are produced in a chemical reaction.

2. Exothermic reactions are accompanied by absorption of Heat.

Which of the statements given above is/are correct?

Solution:
  • During a chemical reaction atoms of one element do not change into those of another element.

  • Nor do atoms disappear from the mixture or appear from elsewhere, in fact chemical reactions involve the breaking and making of bonds between atoms to produce new substances. Exothermic reactions are accompanied by release of Heat.

QUESTION: 2

Which of the following best defines the oxidation of any substance?

Solution: If a substance gains oxygen during a reaction, it is said to be oxidised. If a substance loses oxygen during a reaction, it is said to be reduced. If in a reaction, one reactant gets oxidised while the other gets reduced, it is called oxidation-reduction reactions or redox reactions.

QUESTION: 3

Regarding the oxidation, consider the following statements:

1. The Black coating on silver and the green coating on copper are examples of Corrosion.

2. Bags of chips are flushed with gas such as nitrogen to prevent the chips from getting oxidised.

Which of the statements given above is/are correct?

Solution:
  • When a metal is attacked by substances around it such as moisture, acids, etc., it is said to be corroded and this process is called corrosion. The black coating on silver and the green coating on copper are examples of corrosion.

  • Corrosion causes damage to car bodies, bridges, iron railings, ships and to all objects made up of metals, especially those of iron. When fats and oils are oxidised, they become rancid and their smell and taste change.

  • Usually substances which prevent oxidation (antioxidants) are added to foods containing fats and oil. Keeping food in air tight containers helps to slow down oxidation. Due to this reason, bags of chips are flushed with gas such as nitrogen to prevent the chips from getting oxidised.

QUESTION: 4

Regarding the lime, consider the following statements:

1. Calcium hydroxide is also called as quicklime.

2. Calcium hydroxide reacts slowly with the carbon dioxide in air to form a thin layer of calcium carbonate on the walls after two to three days of whitewashing.

Which of the statements given above is/are correct?

Solution:
  • Calcium oxide is called as quicklime. Calcium oxide reacts vigorously with water to produce slaked lime (calcium hydroxide) releasing a large amount of heat.

  • Calcium hydroxide reacts slowly with the carbon dioxide in air to form a thin layer of calcium carbonate on the walls. Calcium carbonate is formed after two to three days of white washing and gives a shiny finish to the walls.

QUESTION: 5

Respiration is the type of which of the following reactions?

Solution:
  • Respiration is an exothermic process. Reactions in which heat is released along with the formation of products are called exothermic chemical reactions. As we all know, we need energy to stay alive. We get this energy from the food we eat. During digestion, food is broken down into simpler substances.

  • For example, rice, potatoes and bread contain carbohydrates. These carbohydrates are broken down to form glucose. This glucose combines with oxygen in the cells of our body and provides energy.

QUESTION: 6

The neutralization reaction between an acid and a base is a type of:

Solution: A double displacement reaction is a type of reaction in which two reactants exchange ions to form two new compounds. Double displacement reactions typically result in the formation of a product that is a precipitate. Double displacement reactions take the form: AB + CD → AD + CB Key Takeaways

Double Displacement Reaction

1. A double displacement reaction is a type of chemical reaction in which the reactant ions exchange places to form new products.

2. Usually, a double displacement reaction results in precipitate formation.

3. The chemical bonds between the reactants may be either covalent or ionic.

4. A double displacement reaction is also called a double replacement reaction, salt metathesis reaction, or double decomposition.

QUESTION: 7

Which of the following gases is used in the storage of fat and oil containing foods for a long time?

Solution: Helium or nitrogen both can be used for storage of fresh samples of an oil for a long time. These gases are called inert gases as they do not react with most elements including oxygen. Thus these gases create an inert environment for the oil and prevent its reaction with any element in the environment that prevents it from getting rancid.

QUESTION: 8

The respiration process during which glucose undergoes slow combustion by combining with oxygen in the cells of our body to produce energy, is a kind of:

Solution: Its an exothermic process.

QUESTION: 9

A chemical reaction does not involve:

Solution: Changing of the atoms of on element into those of another element to form new products

QUESTION: 10

Consider the following pairs:

Match-I (Homogeneous mixture)

1. Mercury and any other metal

2. Copper and Zinc

3. Copper and tin

4. Lead and Tin

Match-II (Alloy)

Amalgam

Brass

Bronze

Solder

Which of the following pairs given above is/are correctly matched?

Solution:
  • An alloy is a homogeneous mixture of two or more metals, or a metal and a nonmetal. It is prepared by first melting the primary metal, and then, dissolving the other elements in it in definite proportions.

  • It is then cooled to room temperature. If one of the metals is mercury, then the alloy is known as an amalgam. The electrical conductivity and melting point of an alloy is less than that of pure metals.

  • For example, brass, an alloy of copper and zinc (Cu and Zn), and bronze, an alloy of copper and tin (Cu and Sn), are not good conductors of electricity whereas copper is used for making electrical circuits. Solder, an alloy of lead and tin (Pb and Sn), has a low melting point and is used for welding electrical wires together.

QUESTION: 11

Regarding a 'human stomach', consider the following statements:

1. Human stomach produces sulphuric acid that helps in the digestion of food without harming the stomach.

2. During indigestion, the stomach produces too much acid and this causes pain and irritation.

Which of the statements given above is/are correct?

Solution:
  • Our stomach produces hydrochloric acid. It helps in digestion of food without harming the stomach. During indigestion, the stomach produces too much acid and this causes pain and irritation.

  • To get rid of this pain, people use bases called antacids. These antacids neutralise the excess acid. Magnesium hydroxide (Milk of magnesia), a mild base, is often used for this purpose.

QUESTION: 12

Consider the following statements:

1. The human body works within the pH range of 7.0 to 7.8.

2. When pH of rain water is less than 5.6, it is called acid rain.

3. Tooth decay starts when the pH value of the mouth increases.

Which of the statements given above is/are correct?

Solution:
  • Our body works within the pH range of 7.0 to 7.8. Living organisms can survive only in a narrow range of pH change. When pH of rain water is less than 5.6, it is called acid rain. When acid rain flows into the rivers, it lowers the pH of the river water.

  • The survival of aquatic life in such rivers becomes difficult. Tooth decay starts when pH of the mouth is lower than 5.5. Tooth enamel, made up of calcium phosphate is the hardest substance in the body.

  • It does not dissolve in water, but gets corroded when the pH level in the mouth goes below 5.5. Using toothpastes, which are generally basic, for cleaning the teeth can neutralise the excess acid and thus can prevent tooth decay.

QUESTION: 13

Match List-I with List-II and using the code given below, select the correct answer:

List-I (matter)

A. Human blood

B. Milk

C. Human saliva

D. Human Urine

List-II (pH value)

1. 5.5 to 7.5

2. 7.3 to 7.5

3. 6.4

4. 6.5 to 7.5

Code:

Solution: The correct combination of the above list is as follows: (Substance) – (pH value) Human blood – 7.3 to 7.5 Milk – 6.4 Human saliva – 5.5 to 7.5 Human urine – 6.5 to 7.5 In addition, Lemon juice – 2.2 (approx) Gastric juice – 1.2 (approx.) Blood – 7.4 Pure water – 7 Sodium Hydroxide– 14 (Approx.) Milk of magnesia– 10

QUESTION: 14

Match List-I with List-II and using the code given below, select the correct answer:

List I (Natural source)

A. Bee sting

B. Tamarind

C. Tomato

D. Vinegar

List II (Acid)

1. Tartaric acid

2. Methanoic acid

3. Acetic acid

4. Oxalic acid

Solution: Correct combination of the above list with some other important natural sources containing acids is as follow: Natural source Acid Vinegar Acetic acid Orange Citric acid Tamarind Tartaric acid Tomato Oxalic acid Sour milk (Curd) Lactic acid Lemon Citric acid Ant sting Methanoic acid Nettle sting Methanoic

QUESTION: 15

Which of the following is used in a soda-acid fire extinguisher?

Solution: Baking soda is also known as sodium hydrogen carbonate (NaHCO3), sodium bicarbonate, sweet soda and food soda. It is also an ingredient of antacids. Due to its alkaline nature, it relieves the depression of excessive acid in the stomach.It is also used in soda-acid fire extinguishers.