How many methylol groups are present in a typical novolac molecule?
  • a) 3-5
  • b) 6-8
  • c) 0
  • d) 2
If the resinification reaction is stopped at early stages, a low molecular weight product A, having 3-4 aromatic rings and 3-5 methylol groups, which is soluble in alkalis and alcohol is formed. What is the name of the product A?
  • a) resole
  • b) resitol
  • c) resite
  • d) novolac
What is the name of the B- staged resin formed in resinification process?
  • a) resol
  • b) resitol
  • c) resite
  • d) novolac
Resin P, on further heating turns into completely cross-linked resin Q, which is totally insoluble and infusible. Resin P is slightly heat fusible and insoluble in alkalis and alcohols but partly soluble in acetone. What are the names of resin P and Q?
  • a) resol and resitol
  • b) resitol and resite
  • c) resol and resite
  • d) none of the mentioned
Which of the following phenolic resins are suitable for the decorative laminates?
  • a) caustic soda catalyzed resols
  • b) ammonia catalyzed resols
  • c) spirit resols
  • d) resites
What are the temperature and pressure conditions in compression moulding technique in the moulding of phenolic moulding powder?
  • a) 160-170 ᵒC and 1500-3000 psi
  • b) 100-120 ᵒC and 1000-1500 psi
  • c) 160-170 ᵒC and 500-1000 psi
  • d) 100-200 ᵒC and 1500-3000 psi
What is the approximate phenol formaldehyde ratio used is the preparation of casting grade phenolic resins?
  • a) 1:2.2
  • b) 2:1
  • c) 3:1
  • d) 1:2
Why is a stainless steel kettle used in the production of casting grade phenolics?
  • a) to minimize corrosion’
  • b) to minimize color formation
  • c) to maximize color formation
  • d) to increase strength
What type of phenolics is extensively used as objects of art and jewellery?
  • a) laminated phenolics
  • b) cast phenolics
  • c) oil-soluble phenolics
  • d) resols
How is the cross-linking of novolacs better accomplished along with the presence of additional formaldehyde?
  • a) use of acidic catalyst
  • b) use of basic catalyst
  • c) additional phenol
  • d) none of the mentioned
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