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Which type of medicines are used for treating indigestion?
  • a)
    Antibiotic
  • b)
    Analgesic
  • c)
    Antacid
  • d)
    Antiseptic
Correct answer is option 'C'. Can you explain this answer?

Gowri Patel answered
Understanding Indigestion
Indigestion, often characterized by discomfort or pain in the stomach, can result from various factors including diet, stress, and underlying health conditions. It commonly leads to symptoms such as bloating, gas, and nausea.
Types of Medicines for Indigestion
When it comes to treating indigestion, different types of medications serve specific purposes. Here’s a breakdown of the options provided:
  • Antibiotic: These are used to treat bacterial infections and are not typically effective for indigestion, which is often due to non-infectious causes.
  • Analgesic: These medications relieve pain but do not address the underlying issues of indigestion.
  • Antacid: Correct answer. Antacids are specifically formulated to neutralize stomach acid, providing quick relief from indigestion symptoms like heartburn and discomfort.
  • Antiseptic: These are designed to kill or inhibit the growth of microorganisms and are not applicable to the treatment of indigestion.

Why Antacids are Effective
Antacids work by:
  • Neutralizing gastric acid, helping to alleviate symptoms.
  • Providing a rapid onset of relief for heartburn and acid reflux.
  • Containing ingredients such as magnesium hydroxide, aluminum hydroxide, or calcium carbonate, which effectively soothe an upset stomach.

Conclusion
In summary, antacids are the most appropriate medication for treating indigestion due to their ability to neutralize stomach acid and provide quick relief. Understanding the different types of medications helps in choosing the right treatment for indigestion effectively.

Which acid does an ant sting possess?
  • a)
    Methanoic acid
  • b)
    Oxalic acid
  • c)
    Lactic acid
  • d)
    Citric acid
Correct answer is option 'A'. Can you explain this answer?

The correct answer is Methanoic acid.
  • The acid present in an ant sting is Formic acid.
  • Formic acid (systematically called methanoic acid) is the simplest carboxylic acid.
  • Molecular formula: HCOOH
  • It is quite fatal for those ants as after stinging, their stinger is lost and they forcibly release formic acid from their poison gland.
Important Points
  • Oxalic acid is an organic compound found in many plants. These include leafy greens, vegetables, fruits, cocoa, nuts, and seeds
  • Lactic acid is a natural organic acid, found in milk and other food products such as meat and beer.
    • It is used in the food industry as a preservative, flavor enhancer, and acid adjustment.
  • Citric acid is found naturally in citrus fruits, like lemons and limes.
    • It gives them their tart, sour taste.

3 Solutions A, B and C are taken in a test tube. On adding China rose indicator, A turned green, B remained colourlers whereas C turned dark pink in colour.
What is the nature of A, B and C ?
  • a)
    A - Acidic, B- Basic, C - Salt
  • b)
    A - Basic, B - Acidic, C - Salt
  • c)
    A - Salt, B - Basic, C - Acidic
  • d)
    A - Basic, B - Salt, C -Acidic
Correct answer is option 'D'. Can you explain this answer?

Dipika Gupta answered
Understanding China Rose Indicator
The China rose indicator is a natural pH indicator derived from the petals of the China rose plant. It changes color based on the acidity or basicity of the solution it is added to.
Color Changes Indicating pH
- Green: Indicates a basic (alkaline) solution.
- Colorless: Suggests a neutral solution (neither acidic nor basic).
- Dark Pink: Signifies an acidic solution.
Analysis of Solutions A, B, and C
1. Solution A:
- Observation: Turned green.
- Conclusion: A basic solution.
2. Solution B:
- Observation: Remained colorless.
- Conclusion: A neutral solution, likely a salt.
3. Solution C:
- Observation: Turned dark pink.
- Conclusion: An acidic solution.
Final Classification of Solutions
- A: Basic
- B: Salt
- C: Acidic
Thus, the correct classification aligns with option 'D':
- A - Basic
- B - Salt
- C - Acidic
Summary
The responses to the China rose indicator clearly show the nature of each solution:
- A is basic as indicated by the green color.
- B is neutral (salt) since it remains colorless.
- C is acidic, demonstrated by the dark pink color.
Understanding these properties aids in the identification and classification of chemical substances based on their pH levels.

Which of the following substances can be used for identifying an acid solution?
  • a)
    NaCl
  • b)
    Na2CO3
  • c)
    KNO3
  • d)
    K2SO4
Correct answer is option 'B'. Can you explain this answer?

Upsc Toppers answered
Sodium carbonate reacts with an acid to produce carbon dioxide gas, visible as effervescence. For example, Na2CO3 + 2HCl → 2NaCl + H2O + CO2. The evolution of CO2 confirms the presence of an acid.

When lime juice is dropped on baking soda, brisk effervescence takes place because the gas evolved is
  • a)
    Hydrogen
  • b)
    1. Oxygen
  • c)
    Carbon dioxide
  • d)
    None of the above
Correct answer is option 'C'. Can you explain this answer?

  • Lime juice is basically citric acid found in lemon and baking soda is Sodium Bicarbonate. 
  • When these two react, salt and water along with carbon dioxide are formed. 
  • This carbon dioxide is the reason for brisk effervescence observed when the reaction takes place. 
  • Carbon dioxide is a heat-trapping gas released in large quantities from the burning of fossil fuels, industries, and other human activities. 
  • C6H8O7 (Citric Acid) + 3NaHCO3 (Baking Soda) ⇒ 3CO2(gas) + 3H2O (water) + Na3C6H5O7 (Salt- Sodium citrate)

Which of the following acid is found in Nettle plant?
  • a)
    Methanoic acid
  • b)
    Citric Acid
  • c)
    Ethanoic Acid
  • d)
    Oxalic acid
Correct answer is option 'A'. Can you explain this answer?

  • Nettle is an herbaceous plant that grows in the wild.
  • Nettle leaves have stinging hair, which causes painful stings when touched accidentally. 
  • This is due to the methanoic acid secreted by them. 
  • A traditional remedy is rubbing the area with the leaf of the dock plant, which often grows beside the nettle.

Lemon fruit is a rich source of 
  • a)
    malic acid
  • b)
    citric acid
  • c)
    tartaric acid
  • d)
    acetic acid
Correct answer is option 'B'. Can you explain this answer?

Lemon fruit is a rich source of citric acid.
  • Citric acid is a weak organic acid.
  • It is a six-carbon tricarboxylic acid.
  • A manufactured form of citric acid is commonly used as an additive in food, cleaning agents, and nutritional supplements.
  • Citric acid is mainly produced by fungal fermentation.
  • Chemical synthesis of citric acid is possible, but it is expensive than fungal fermentation.

What is the pH value of acid rain?
  • a)
    Less than 5.6
  • b)
    More than 5.6
  • c)
    Equal to 7.0 
  • d)
    5.62. More than 5.63. Equal to 7.0 
Correct answer is option 'A'. Can you explain this answer?

  • Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are discharged into the air.
  • These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.
  • Human activities are the main cause of acid rain.
  • Over the past few decades, humans have released so many different chemicals into the air that they have changed the mix of gases in the atmosphere.
  • Power plants release the majority of sulfur dioxide and much of the nitrogen oxides when they burn fossil fuels, such as coal, to produce electricity.
  • Besides, the exhausts from cars, trucks, and buses release nitrogen oxides and sulfur dioxide into the air. These pollutants cause acid rain.

Which colour appears when few drops of phenolphthalein are put into a test tube containing lime water?
  • a)
    Yellow
  • b)
    Pink
  • c)
    Orange
  • d)
    Colourless
Correct answer is option 'B'. Can you explain this answer?

  • The chemical compound phenolphthalein has the formula C20H14O4 and is commonly abbreviated as "HIn" or "phph" in shorthand notation.
  • Phenolphthalein is frequently used as an indicator.
  • It's a phthalein dye, which means it's a type of dye.
  • Phenolphthalein in Acidic solutions turns colourless
  • Phenolphthalein in basic solutions turns pink in colour. 
Explanation:
  • Lime water is basic in nature. 
  • Calcium hydroxide is the chemical term for lime water, which has the formula Ca(OH)2.
  • When Phenolphthalein, it turns pink as lime water is basic in nature.
  • Hence, the correct answer is - Pink.

Which of the following acid is found in human stomach?
  • a)
    Hydrochloric acid
  • b)
    Sulfuric acid
  • c)
    Nitric acid
  • d)
    Acetic acid
Correct answer is option 'A'. Can you explain this answer?

  • Hydrochloric acid is found in the human stomach.
  • Formula- HCl
  • Hydrochloric acid helps in digestion by breaking complex large food molecules into simpler molecules.
  • The acid activates the pepsinogen enzyme required to digest proteins.
  • It also kills harmful microorganisms present in the stomach.
  • It is also known as muriatic acid

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