SOLVED PAPER 2020 (CDS) (II) (General Studies)

Total Questions: 120

111. The radioactive isotope of hydrogen is

Correct Answer: (c) tritium
Solution:Tritium is the radioactive isotope of hydrogen. The nucleus of tritium contains one proton and two neutrons. It is represented as 3H or T. It is used as a radioactive tracer, in radioluminescent light sources for watches and instruments.

112. Which one of the following is used for storing biological tissues?

Correct Answer: (a) Liquid nitrogen
Solution:Liquid nitrogen is used for storing biological tissues. This process is known as Cryo preservation. In this process, organelles, cells tissues or other biological lonsbuets susceptible to damage caused by unregulate Chemical kinetics are preserved by cooling to very low temperatures.

113. Which one of the following does not form oxide on reaction with oxygen?

Correct Answer: (c) Tin
Solution:

Tin (Sn) does not form oxide on reaction with oxygen. It readily form peroxide. Complete reaction is

114. The valency of phosphorus is

Correct Answer: (d) 3, 5
Solution:Valency of phosphorus is 3, 5-orbits are stable when they are fully filled or half filled. So, to attain a stable configuration it can take 3 electrons or remove 5 electrons. So, valency of ‘P’ is 3 and 5.

115. Lead nitrate on heating gives

Correct Answer: (b) PbO and NO₂
Solution:

Lead nitrate on heating gives PbO (lead oxide) and NO₂ (nitrogen dioxide). Complete reaction is as follows

116. Which one of the following is a decommissioned aircraft carrier?

Correct Answer: (d) INS Viraat
Solution:Amongst the given options, INS Viraat is a decommissioned aircraft carrier. It was a Centaur-class aircraft carrier of the Indian Navy. India acquired this aircraft carrier from England and commissioned into the Indian Navy on May 12th, 1987. Viraat was formally decommissioned on March 6th, 2017.

INS Khanderi is a Kalvari-class submarine, built in India. INS Rajput is a guided-missile destroyer. INS Chakra is a nuclear-powered attack submarine.

117. Who among the following has won the Singles Title in Wimbledon Tennis Championship (Women) in the year 2019?

Correct Answer: (b) Simona Halep
Solution:

Simona Halep (Romania) won the Women’s Singles title in Wimbledon Tennis Championship in the year 2019.

118. Recently islands of Andaman and Nicobar were connected with mainland by Submarine Optical Fibre Cable. Which one of the following islands was not connected initially?

Correct Answer: (a) Shaheed Island
Solution:n August 2020, submarine Optical Fibre Cable (OFC) connecting Andaman and Nicobar Islands to the mainland was inaugurated. Services began from Chennai to Port Blair, Port Blair to Little Andaman and Port Blair to Swaraj Island. Hence, Shaheed Island was not connected initially. The project of laying 2300 km optical fibre started in December, 2018.

A submarine optical fibre communications cable is a cable laid on the seabed between land-based stations to transmit telecommunication signals across stretches of ocean and sea.

119. In August 2020, who among the following was administered the oath as the Prime Minister of Sri Lanka for the fourth time?

Correct Answer: (c) Mahinda Rajapaksa
Solution:Mahinda Rajapaksa was administered oath as the Prime Minister of Sri Lanka for the fourth time in August 2020. He is leader of Sri Lanka People’s Party (SLPP) leader. His party registered victory in 145 constituencies, bagging a total of 150 seats with its allies, a two-thirds majority in the 225-member Parliament. He has replaced Ranil Wickremesinghe.Mahinda Rajapaksa was sworn in as the Prime Minister for the first time on 6th April, 2004.

120. Which one of the following Indian Ocean island nations has recently declared a State of environmental emergency due to oil spill from a grounded ship?

Correct Answer: (a) Maldives
Solution:Mauritius is an island nation in the Indian Ocean, which declared a state of emergency due to oil spill in August 2020. A japanese bulk-carrier ship MV Wakashio which was carrying fuel oil had split into two parts near Blue Bay Marine Park in South-East Mauritius. It caused leakage of over 1000 tonnes of oil. It endangers the already endangered coral reefs, seagrasses, mangroves, the fishes and other aquatic fauna.