A rectified spirit, rectified alcohol, or neutral spirit is highly concentrated ethanol which has been purified by means of repeated distillation, a process that is called rectification. It typically contains 95% alcohol by volume (ABV). Rectified spirits are used in mixed drinks, in the production of liqueurs, for medicinal purposes, and as a household solvent. The purity of rectified spirit has a practical limit of 95.6% ABV (191.2 US proof) when produced using conventional distillation processes, because a mixture of ethanol and water becomes an azeotrope at this concentration. Neutral grain spirits are rectified spirits made from grain. However, rectified spirits are also made from other kinds of plant material, such as sugar beets, potatoes, and sugar cane.

Correct Option: A

A rectified spirit, rectified alcohol, or neutral spirit is highly concentrated ethanol which has been purified by means of repeated distillation, a process that is called rectification. It typically contains 95% alcohol by volume (ABV). Rectified spirits are used in mixed drinks, in the production of liqueurs, for medicinal purposes, and as a household solvent. The purity of rectified spirit has a practical limit of 95.6% ABV (191.2 US proof) when produced using conventional distillation processes, because a mixture of ethanol and water becomes an azeotrope at this concentration. Neutral grain spirits are rectified spirits made from grain. However, rectified spirits are also made from other kinds of plant material, such as sugar beets, potatoes, and sugar cane.

The candle can be made of paraffin (a byproduct of petroleum refining), microcrystalline wax, stearin (now produced almost exclusively from palm waxes though initially manufactured from animal fats), beeswax (a byproduct of honey collection), gel (a mixture of polymer and mineral oil), some plant waxes (generally palm, carnauba, bayberry, or soybean wax), tallow (rarely used since the introduction of affordable and cheap wax alternatives) or spermaceti (extracted from the head of a Sperm Whale). The size of the flame and corresponding rate of burning is controlled largely by the candle wick. The most basic production method of candles generally entails melting the solid fuel by the controlled application of heat. The liquid is then poured into a mould or a wick is repeatedly immersed in the liquid to create a dipped tapered candle. Often fragrance oils, essential oils or anilinebased dye is added.

Correct Option: A

The candle can be made of paraffin (a byproduct of petroleum refining), microcrystalline wax, stearin (now produced almost exclusively from palm waxes though initially manufactured from animal fats), beeswax (a byproduct of honey collection), gel (a mixture of polymer and mineral oil), some plant waxes (generally palm, carnauba, bayberry, or soybean wax), tallow (rarely used since the introduction of affordable and cheap wax alternatives) or spermaceti (extracted from the head of a Sperm Whale). The size of the flame and corresponding rate of burning is controlled largely by the candle wick. The most basic production method of candles generally entails melting the solid fuel by the controlled application of heat. The liquid is then poured into a mould or a wick is repeatedly immersed in the liquid to create a dipped tapered candle. Often fragrance oils, essential oils or anilinebased dye is added.

The greenhouse effect is a process by which thermal radiation from a planetary surface is absorbed by atmospheric greenhouse gases, and is re-radiated in all directions. Since part of this re-radiation is back towards the surface and the lower atmosphere, it results in an elevation of the average surface temperature above what it would be in the absence of the gases. The environmental effects of carbon dioxide are of significant interest. In the earth’s atmosphere, it acts as a greenhouse gas which plays a major role in global warming and anthropogenic climate change. Also a major source of ocean acidification is CO2 which dissolves in water forming carbonic acid, which is a weak acid, because CO2 molecule ionization in water is incomplete.

Correct Option: B

The greenhouse effect is a process by which thermal radiation from a planetary surface is absorbed by atmospheric greenhouse gases, and is re-radiated in all directions. Since part of this re-radiation is back towards the surface and the lower atmosphere, it results in an elevation of the average surface temperature above what it would be in the absence of the gases. The environmental effects of carbon dioxide are of significant interest. In the earth’s atmosphere, it acts as a greenhouse gas which plays a major role in global warming and anthropogenic climate change. Also a major source of ocean acidification is CO2 which dissolves in water forming carbonic acid, which is a weak acid, because CO2 molecule ionization in water is incomplete.

Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability. Because the nucleus experiences the intense conflict between the two strongest forces in nature, it should not be surprising that there are many nuclear isotopes which are unstable and emit some kind of radiation. The most common types of radiation are called alpha, beta, and gamma radiation, but there are several other varieties of radioactive decay. Among uranium, thorium, radium and cadmium the first three does show radioactive properties while the fourth one does not show any kind of radioactive properties.

Correct Option: D

Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability. Because the nucleus experiences the intense conflict between the two strongest forces in nature, it should not be surprising that there are many nuclear isotopes which are unstable and emit some kind of radiation. The most common types of radiation are called alpha, beta, and gamma radiation, but there are several other varieties of radioactive decay. Among uranium, thorium, radium and cadmium the first three does show radioactive properties while the fourth one does not show any kind of radioactive properties.

A nuclear reactor is a device to initiate and control a sustained nuclear chain reaction. Most commonly they are used for generating electricity and for the propulsion of ships. Usually heat from nuclear fission is passed to a working fluid (water or gas), which runs through turbines that power either ship’s propellers or generators. Some produce isotopes for medical and industrial use, and some are run only for research. When a large fissile atomic nucleus such as U²³⁵ or U²³⁹ absorbs a neutron, it may undergo nuclear fission. The heavy nucleus splits into two or lighter nuclei (the fission products), releasing kinetic energy, gamma radiation and free neutrons. A portion of these neutrons may later be absorbed by other fissile atoms and trigger further fission events, which release more neutrons, and so on. This is known as a nuclear chain reaction.

Correct Option: A

A nuclear reactor is a device to initiate and control a sustained nuclear chain reaction. Most commonly they are used for generating electricity and for the propulsion of ships. Usually heat from nuclear fission is passed to a working fluid (water or gas), which runs through turbines that power either ship’s propellers or generators. Some produce isotopes for medical and industrial use, and some are run only for research. When a large fissile atomic nucleus such as U²³⁵ or U²³⁹ absorbs a neutron, it may undergo nuclear fission. The heavy nucleus splits into two or lighter nuclei (the fission products), releasing kinetic energy, gamma radiation and free neutrons. A portion of these neutrons may later be absorbed by other fissile atoms and trigger further fission events, which release more neutrons, and so on. This is known as a nuclear chain reaction.