Tag: chemistry

Questions Related to chemistry

Which of the following nano materials are examples of  zero dimensional nano materials?

nanochemistry nanotechnology applied chemistry materials chemistry

  1. Diamond

  2. Fullarene

  3. Nano particles

  4. Graphite

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Correct Option: B
Explanation:

Accordingly, in zero-dimensional (0D) nanomaterials all the dimensions are measured within the nanoscale (no dimensions are larger than 100nm). Most commonly, 0D nanomaterials are nanoparticles.
Hence option B is correct.

Which of the following are the nanomaterials with only one dimension between 1 nm and 100 nm?

nanochemistry nanotechnology applied chemistry materials chemistry

  1. Nanolayers

  2. Nanotubes

  3. Nanowires

  4. Nanoparticles

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Correct Option: A
Explanation:

Nanolayers are the nanomaterials with only one dimension between 1 nm and 100 nm. Nanotubes or nanowires are the nanomaterials with two dimension between 1 nm and 100 nm. Nanoparticles are the nanomaterials with three dimension between 1 nm and 100 nm.

In which of the following type of nano material three dimensions are  outside the nano scale technology deals with using?

nanochemistry nanotechnology applied chemistry materials chemistry

  1. One dimensional nano material

  2. Zero dimensional nano material

  3. Two dimensional nano material

  4. Three dimensional nano material

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Correct Option: D
Explanation:

Three-dimensional nanomaterials (3D) are materials that are not confined to the nanoscale in any dimension. This class can contain bulk powders, dispersions of nanoparticles,bundles of nanowires, and nanotubes as well as multi-nanolayers.
Hence option D is correct.

Which of the following are characteristic properties of nano particles?

nanochemistry nanotechnology applied chemistry materials chemistry

  1. More surface area

  2. Quantum effects

  3. Both a and b

  4. None of the above

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Correct Option: C
Explanation:

Two principal factors cause the properties of nanomaterials to differ significantly from other materials: increased relative surface area, and quantum effects. These factors can change or enhance properties such as
reactivity, strength and electrical characteristics.
Hence option C is correct.

Which of the following will not act as antacid?

chemistry medicinal chemistry antacids and antihistamines therapeutic action of different classes of drugs ph regulation of the stomach

  1. Sodium hydrogencarbonate

  2. Magnesium hydroxide

  3. Sodium carbonate

  4. Aluminium carbonate

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Correct Option: C
Explanation:

An antacid is a substance which neutralises stomach acidity and is used to relieve heartburn, indigestion or an upset stomach.
Antacids contain alkaline ions that chemically neutralise stomach gastric acid, reducing damage and relieving pain.
Examples of antacids are-
Sodium hydrogencarbonate,Magnesium hydroxide,Aluminium carbonate,Aluminium hydroxide.

Sodium carbonate known as washing soda is quite alkaline in nature and has a horrid soapy taste. It is not very palatable and could burn the throat. Bicarbonate is much gentler and not as strongly alkaline, and therefor more palatable. Hence, it will not act as Antacid.

The main cause of acidity in the stomach is :

chemistry medicinal chemistry antacids and antihistamines therapeutic action of different classes of drugs ph regulation of the stomach

  1. release of extra gastric acids which decrease the pH level

  2. indigestion and pain in large intestine

  3. increase the pH level in stomach

  4. release of extra bile juice which increases alkaline medium in stomach

Show answer
Correct Option: A
Explanation:

An antacid is a substance which neutralises stomach acidity and is used to relieve heartburn, indigestion or an upset stomach.

Antacids contain alkaline ions that chemically neutralise stomach gastric acid, reducing damage and relieving pain.
Gastric acid is a digestive fluid formed in the stomach and is composed of hydrochloric acid ($HCl$), potassium chloride ($KCl$) and sodium chloride ($NaCl$). If gastric acid is released in the stomach the Ph level decreases and thereby increasing acidity in the stomach.

Which of the following statements is not correct?

chemistry medicinal chemistry antacids and antihistamines therapeutic action of different classes of drugs ph regulation of the stomach

  1. Some disinfectants can be used as antiseptic at low concentration.

  2. Aspirin is analgesic and antipyretic.

  3. Norethindrone is an antihistamine.

  4. Chloramphenicol is a broad spectrum antibiotic.

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Correct Option: C
Explanation:
  • Same substances can act as an antiseptic as well as a disinfectant by varying the concentration. For example, 0.2 per cent solution of phenol is an antiseptic while its one per cent solution is disinfectant.
  • Aspirin acts as both analgesic and Antipyretic.
  • Antihistamines interfere with the natural action of histamine by competing with histamine for binding sites of receptor where histamine exerts its effect. Synthetic drugs, brompheniramine (Dimetapp) and terfenadine (Seldane), act as antihistamines.
  • Norethindrone is an example of a synthetic progesterone derivative most widely used as an antifertility drug.
  • Chloramphenicol is a broad spectrum antibiotic.
  • Hence, option B is not a correct statement.

The pair whose both species are used in antacid medicinal preparation is:

chemistry medicinal chemistry antacids and antihistamines therapeutic action of different classes of drugs ph regulation of the stomach

  1. $NaHCO _3$ nad $Mg(OH) _2$

  2. $Na _2CO _3$ and $Ca(HCO _3) _2$

  3. $Ca(HCO _3) _2$ and $Mg(OH) _2$

  4. $Ca(OH) _2$ and $NaHCO _3$

Show answer
Correct Option: A
Explanation:
  • An antacid is a substance which neutralizes stomach acidity and is used to relieve heartburn, indigestion or an upset stomach.
  • It is also used to relieve symptoms of extra gas such as belching, bloating, and feelings of pressure/discomfort in the stomach/gut. Aluminum and magnesium antacids work quickly to lower the acid in the stomach.
  • Generally $NaHCO _3$ and $Mg(OH) _2$ are used in antacid medicinal preparation.

Cimetidine acts as:

chemistry medicinal chemistry antacids and antihistamines therapeutic action of different classes of drugs ph regulation of the stomach

  1. antibiotic

  2. antifertility drug

  3. antihistamine

  4. antipyretic

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Correct Option: C
Explanation:

Cimetidine is a histamine $H _2$-receptor antagonist, that inhibits stomach acid production. It is largely used in the treatment of heartburn and peptic ulcers. So it acts as an antihistamine.

Aspirine is a an:

chemistry medicinal chemistry antacids and antihistamines therapeutic action of different classes of drugs ph regulation of the stomach

  1. Antiseptic

  2. Antipyretic

  3. Antimalarial

  4. Narcotic

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Correct Option: B
Explanation:

Aspirine is an analgesic (meaning it helps pain), and an antipyretic (meaning it reduces fever.)


Option B is correct