About Chemicals PDF

ABOUT CHEMICALS 1. The stage of processing that rinsed the film in an acid solution to neutralize the residual developer in the emulsion and stops its action STOP BATH 2. It removes water and prepare radiograph for viewing...

ABOUT CHEMICALS 1. The stage of processing that rinsed the film in an acid solution to neutralize the residual developer in the emulsion and stops its action STOP BATH 2. It removes water and prepare radiograph for viewing DRYING 3. This process occurs when an electron is given up by a chemical to neutralize a positive ion (e.g. Ag+ + e = Ag) REDUCTION 4. This chemical provides electrons to the sensitivity center to change the silver ion to silver DEVELOPER 5. It controls the shoulder of the characteristic curve HYDROQUINONE 6. The stage of processing during which the latent image is converted to a visible image DEVELOPING 7. What is the usual cause when the films that drop from the processor are damp? DEPLETION OF THE DEVELOPER HARDENER 8. This term refers to the permanence of the radiograph. The image does not deteriorate with age but remains in its original state ARCHIVAL QUALITY 9. The stage of processing that removes excess chemicals in the film from previous processing steps _______________ WASHING 10-11. These can accelerate the oxidation of the hydroquinone, rendering the developer unstable _______________ METALLIC IMPURITIES & SOLUBLE SALTS 12. The stage of processing that clears the unexposed SHC from the emulsion and hardening the emulsion to preserve the image FIXING 13. It acts rapidly and influences the lighter shades of gray PHENIDONE 14. This fixing component accelerates the shrinking of the emulsion and causes it to become more rigid HARDENER 15 This is the cause of excessive hypo retention INADEQUATE WASHING 16. The stage of processing that allows water to penetrate the gelatin of the emulsion, causing it to swell. WETTING 17. It is engaged at the entrance rollers to control the replenishment rate of the processing chemicals WETTING 18. It controls the toe of the characteristic curve PHENIDONE 19. This developer component is used to control aerial oxidation, helps maintain the proper development rate and causes the developer remain clear PRESERVATIVE 20. This is the universal solvent WATER 21. This fixing component helps maintain proper pH so that the alkalinity and acidity in the fixer must remain constant BUFFER 22. It refers to the undesirable retention of the fixer in the emulsion HYPO RETENTION 23. The principal action of this chemical is to change the silver ions of exposed silver halide crystals into metallic silver DEVELOPER 24. This developer component enhances the action of developing agent by producing alkalinity and controlling the pH ACTIVATOR 25. It is introduced into the chemistry when it is mixed, handled and stored AIR 26. This developer component is used to remove metallic impurities and soluble salts to stabilize the developing agent SEQUESTERING AGENT 27. A reaction that produces electron OXIDATION 28. This material is required in the replenishment tank to for the control of aerial oxidation CLOSE-FITTING FLOATING LIDS 29. The stage of processing that produces film of archival quality FIXING 30. This fixing component ensures that the film is transported properly through the wash-and-dry section and that rapid and complete drying occurs HARDENER 31. It occurs when the action of two agents working together is greater than the sum of the action of each agent working independently SYNERGISM 32. Oxidized developing agents appears ______ BROWNISH 33. The ______ dimension of the film should always be against the side rail, so the proper replenishment rate is maintained SHORTER OR SHORT SIDE 34. This is the principal component of the developer HYDROQUINONE 35. What is the replenishment rate of the developer for every 35 cm or 14 in. of film? 60-70 Ml/ 35 cm OR 14 in 36. This is the strongest alkali and commonly known as lye _______________ SODIUM HYDROXIDE 37. This is the most common cause of poor archival quality SILVER SULFIDE STAIN 38. This fixing component helps maintain chemical balance because of the carryover of developer and fixer from one tank to another PRESERVATIVE 39. What is the power capacity in watts of the 3 heating coils in the drying system? 2500 W 40. What is the size of a transport roller in mm? 25 nm ( 1 INCH) 41. This stage of processing removes any residual chemicals such as hypo that clings to the surface of the film WASHING 42. This developer component restricts the action of the developing agent to only those silver halide crystals that have been irradiated RESTRAINER 43. This is where the transport system begins and where the film to be processed is inserted into the automatic processor in the darkroom FEED TRAY 44. What is the minimum flow rate for the wash tank in most processors? 12 L/ min OR 3 gal/min 45. This fixing component removes unexposed and undeveloped SHC from the emulsion _______________ FIXING AGENT 46. What is the replenishment rate of the fixer for every 35 cm or 14 in. of film? 100-110 Ml/ 35 cm OR 14 in. 47. A type of fog that occurs when the unexposed SHC are reduced to metallic silver DEVELOPMENT/ CHEMICAL FOG 48. This developer component controls emulsion swelling and softening and helps the film to transport properly to the automatic processor HARDENER 49. This fixing component helps removes the principal impurities, aluminum ions, at this stage SEQUESTERING AGENT 50. It acts slowly but is responsible for the very blackest shades HYDROQUINONE Enumeration: Write your answer in separate sheets of paper 1. What are the 3 terms used interchangeably in reference to the fixing agent? 1. HYPO 2. CLEARING AGENT 3. THIOSULFATE What are the 2 chemicals that works synergistically to shape the characteristic curve of a radiograph? 1. PHENIDONE 2. HYDROQUINONE What are the 5 principal components of an automatic processor? 1. TRANSPORT SYSTEM 2. TEMPERATURE CONTROL SYSTEM 3. CIRCULATION SYSTEM 4. REPLENISHMENT SYSTEM 5. DRYER SYSTEM. Prepared By: Meynard Y. Castro, RRT, MSRT Assistant Lecturer III, Institute of Imaging Health Sciences University of Makati