48.

47,

48,

49.

50.

51.

52,

sorted paper then has to be repulped or mixed with water and broken down into its
individual fibres. This mixture is called stock and may contain a wide variety of
contaminating materials, particularly if it is made from mixed waste paper which has
had little sorting various machinery is used to remove other materials from the stock.
After passing through the re-pulping process, fibres from printed waste paper are grey
in colour because the printing ink has soaked into the individual fibres. This recycled
material can only be used in products where the grey colour does not matter, such as
cardboard boxes but if the grey colour is not acceptable, the fibres must be de-inked.
This involves adding chemicals such as caustic soda or other alkalies, soaps and
detergents, water-hardening agents such as calcium chloride, frothing agents and
bleaching agents. Before the recycled fibres can be made into paper they must be
refined or treated in such a way that they bond together. Most paper products must
contain some virgin fibre as well as recycled fibres and unlike glass, paper cannot ‏عدا‎
‎recycled indefinitely, Most paper is down-cveled which means that a product made
from recveled paper is of an inferior quality to the original paper. Recvcling paper is
beneficial in that it saves some of the energy, labour and capital that goes into producing
virgin pulp. However, recycling requires the use of fossil fuel, a non-renewable energy
source, to collect the waste paper from the community and to process it to produce
new paper and the recycling process still creates emissions which require treatment
before they can be disposed of safety. (700 words)

12 6 (L resistors are connected in series to a 9V batterv. Find the intensity of current
through each resistor ?

What is Njattuvela ?
What is the difference between liquor ammonia and liguid ammonia ?
State Faraday's law of Electrolysis ?

Find out the number of turns in the secondary coil of a stepdown transformer of output
voltage 18 V and input voltage 240 V and having 8000 turns in the primary coil ?

Name the monomer of PVC. Write the equation of polymerisation reaction producing
PVC.

CNG is used as a fuel in a number of vehicles in Delhi. Write two advantages of CNG
over petral and diesel,

5 154/2016
மா.)