D425 Introduction to Chemistry - Set 3 - Part 3

Correct Answer: Light sensitivity

Option b is correct because silver halides undergo photochemical changes when exposed to light, recording the image latently.
Option a is incorrect because silver halides produce black and white images; color requires different dye-coupling chemistry additionally employed.
Option c is incorrect because the photographic process uses light energy, not heat generation, to create image formation occurring.
Option d is incorrect because photography is optical and chemical, not magnetic; silver halides respond to light, not magnetism.

Correct Answer: Glass formation

Option b is correct because molten glaze ingredients cool to form glassy coating, providing waterproofing and decoration simultaneously.
Option a is incorrect because materials melt and solidify, not evaporate; the glaze becomes a permanent glass layer formed.
Option c is incorrect because while glazes contain metal oxides for color, the coating is glass, not metallic deposits.
Option d is incorrect because glazes are inorganic glass, not plastic; they form through high-temperature fusion, not polymer application.

Correct Answer: Increases dramatically

Option b is correct because phosphorus provides extra electrons, creating n-type semiconductor with greatly enhanced electrical conductivity achieved.
Option a is incorrect because doping increases, not decreases conductivity; pure silicon is more insulating than doped silicon material.
Option c is incorrect because even tiny dopant amounts cause dramatic conductivity changes, the basis of semiconductor technology applications.
Option d is incorrect because doping affects electrical, not magnetic properties; semiconductors don't become ferromagnetic through phosphorus doping typically.

Correct Answer: Oxidation reaction

Option b is correct because ethanol oxidizes to acetaldehyde or acetic acid, causing color change in the detection reagent.
Option a is incorrect because the detection involves chemical reaction with new products formed, not just physical phase transitions.
Option c is incorrect because alcohol detection uses chemical reactions, not magnetic properties; ethanol isn't magnetic at all.
Option d is incorrect because breathalyzers detect dissolved ethanol through reactions, not crystal formation or growth processes involved.

Correct Answer: Sacrificial protection

Option b is correct because zinc preferentially corrodes instead of steel, providing cathodic protection through electrochemical sacrifice occurring.
Option a is incorrect because protection is electrochemical, not visual; color doesn't prevent corrosion of the underlying steel metal.
Option c is incorrect because corrosion protection is electrochemical, not magnetic; zinc doesn't shield steel from magnetic fields.
Option d is incorrect because zinc's protection is electrochemical, not thermal; temperature insulation doesn't prevent electrochemical corrosion reactions.

Correct Answer: Temperature control

Option b is correct because temperature affects yeast metabolism, determining product formation and preventing off-flavors from developing excessively.
Option a is incorrect because container color doesn't affect yeast biochemistry; temperature and nutrients control fermentation products formed internally.
Option c is incorrect because vessel shape affects circulation but temperature is more critical for controlling yeast metabolism pathways.
Option d is incorrect because fermentation occurs in darkness typically; temperature, not light, controls yeast metabolic pathways primarily.

Correct Answer: Hydrogel structure

Option b is correct because hydrogel polymers hold water for comfort while maintaining porosity for oxygen permeation through material.
Option a is incorrect because tinting is cosmetic or UV protection; oxygen permeability comes from material structure, not color.
Option c is incorrect because metal coatings would block oxygen and irritate eyes; soft lenses use permeable polymers instead.
Option d is incorrect because contact lenses are amorphous hydrogels, not crystalline; flexibility and permeability require non-crystalline structure maintained.

Correct Answer: Dimensional collapse

Option b is correct because water replacement during drying causes cell wall collapse unless specially treated with consolidants.
Option a is incorrect because structural collapse, not color change, is the primary challenge when drying waterlogged wood artifacts.
Option c is incorrect because weight decreases during drying; the problem is structural collapse, not weight gain occurring.
Option d is incorrect because wood is organic; metal content isn't the issue, cellular collapse during water removal is.

Correct Answer: Mild conditions

Option b is correct because enzymes work at moderate temperature and neutral conditions, reducing energy and equipment costs significantly.
Option a is incorrect because color is irrelevant to conversion efficiency; the advantage is mild reaction conditions, not appearance.
Option c is incorrect because enzymatic conversion works at atmospheric pressure; high pressure would denature enzymes, reducing activity.
Option d is incorrect because enzymes are proteins, not metals; their advantage is specificity under mild conditions, not metallic catalysis.

Correct Answer: Reversible ion insertion

Option b is correct because ion insertion changes oxidation state and electronic structure, altering optical properties reversibly when powered.
Option a is incorrect because the materials remain solid; optical changes occur through electronic, not phase transitions at temperature.
Option c is incorrect because electrochromic behavior depends on oxidation state changes, not magnetic properties of the materials involved.
Option d is incorrect because the effect is electronic, not structural; crystal size doesn't change during the switching process.