Chemistry - Study Mode

[#456] Which of the following laser types is used in a laser printer?
Correct Answer

(B) Semiconductor laser

Explanation

Solution: A semiconductor diode laser is currently used in laser printers as the light source.

[#457] The chemical that is used to ripen mangoes is
Correct Answer

(B) Calcium carbide

Explanation

Solution: Pouches of calcium carbide are placed with mangoes. When this chemical comes in contact with moisture, acetylene gas is produced, the effects of which are similar to ethylene, the one that is naturally used for fruit ripening process.

[#458] Exposure to mixtures of chemicals are greater than expected on the basis of effects of exposure to each chemical individually. This is known as
Correct Answer

(C) Synergism

Explanation

Solution: When the toxic effect of the mixture is greater than that expected for the sum of individual constituent doses, which is that effects of combined doses are more-than-additive, the interactions are said to be synergistic. Conversely, when the toxic effect of the mixture is less than that expected under the dose additivity assumption, the interactions are said to be antagonistic.

[#459] Which of the following is used to remove ink and rust stains on cloth?
Correct Answer

(A) Oxalic acid

Explanation

Solution: Oxalic acid is a reducing agent and its conjugate base, known as oxalate, is a chelating agent for metal cations and stain removal. Oxalic acid's main applications include cleaning or bleaching, removal of stains on clothes and the removal of rust.

[#460] KMnO 4 can be used as a/an
Correct Answer

(D) Disinfectant

Explanation

Solution: KMnO 4 can be used as a disinfectant.