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Correct ANSWER is (c) NICKEL, iron

Explanation: Nickel and copper are two frequently found impurities in magnesium ALLOYS. The impact of the CORROSION resistance of the material and MUST be limited. Another impurity found in magnesium alloys is copper.

Right answer is (d) carbon monoxide

To explain: Carbothermic process is a thermal process USED in the extraction of magnesium from its ORES. In its process, magnesium oxide is obtained through a reduction from ores and is HEATED. It produces carbon monoxide APART from magnesium.

Right choice is (c) 650°C

To ELABORATE: The melting point of magnesium is 650° Celsius. The melting point of a solid OBJECT INDICATES the point at which it will melt. The melting point of titanium is 1668° Celsius and that of lead is 327° Celsius.

The CORRECT choice is (a) 1.8

For EXPLANATION I would say: The specific GRAVITY of an object REFERS to the RATIO of the density of that object to the density of a reference object. The specific gravity of magnesium is 1.8. The specific gravity of aluminium is 2.7 and steel is 7.9.

The correct choice is (a) 99.99%

The best explanation: Magnesium is EXTRACTED through the ores FOUND in places ACROSS the world. It is desirable to have a high amount of magnesium in its EXTRACTION. Magnesium obtained through the ferrosilicon process can have a minimum PURITY of 99.99%.

Right choice is (a) 6,500,000 p.s.i

To ELABORATE: The MODULUS of elasticity can be described as the RESISTANCE of a SUBSTANCE to elastic deformation when it is subjected to STRESS. The modulus of elasticity of magnesium is 6,500,000 p.s.i and that of aluminium is 4,350,000 p.s.i.

Right option is (d) minimum

Explanation: Magnesium is used in making several components ACROSS INDUSTRIES in the world. Considering its physical and chemical PROPERTIES, it should be used when strength is not the primary criteria and minimum THICKNESS is required.

Correct option is (c) 0.125%

To explain I WOULD say: Magnesium is found in several parts of the world as ores. It is also present in water BODIES. Magnesium CONSTITUTES around 0.125% of ocean water. The SLAT lake city of Utah, U.S.A CONTAINS 0.56% magnesium.

Correct answer is (C) Ferrosilicon process

For EXPLANATION I would say: Magnesium is not FOUND in a PURE state. It has to be extracted from its ores. This can be DONE using several processes. Ferrosilicon process is a thermal reduction process used to extract magnesium.

Right answer is (c) 24.3 u

The explanation: Magnesium is a very LIGHTWEIGHT MATERIAL compared to other materials LIKE titanium and chromium. It does not have high strength. The atomic mass of magnesium is 24.3 u and titanium is 47.86 u.

Right option is (C) USA, Greece

For EXPLANATION I WOULD say: Magnesium is found in the FORM of ores in several places around the world. From the ores, magnesium is extracted. Magnesium can be found in Greece, the united states and several other COUNTRIES.

Right choice is (c) die castings and permanent mold

Best explanation: Magnesium alloys can be machined easily. They can also be fabricated into SEVERAL structural shapes. They are ATTAINABLE in the form of die castings, permanent MOULD and several other VARIANTS.

Correct choice is (B) False

Best explanation: The above statement is incorrect. Magnesium can be used in making GEARBOXES, HAND DRILLS, PNEUMATIC nail guns, chain saws, simple hand tools etc. as it can withstand elevated temperatures and high energies.

Correct ANSWER is (C) 99.98%

For explanation I would SAY: Electrolytic process is one of the SEVERAL processes used to extract magnesium from seawater, brine or any other ores. If it is NECESSARY this process can yield magnesium with a minimum purity of 99.98%.

Right choice is (b) False

To elaborate: The above statement is INCORRECT. Magnesium is not frequently found in its natural STATE, in fact, it is never found in its natural state. It is found in ORES and has to be processed to obtain pure magnesium.

The correct answer is (a) True

To ELABORATE: The above statement is correct. MAGNESIUM and magnesium alloys are utilized in several INDUSTRIES across the world. For example, it is used in the automobile INDUSTRY, ELECTRICAL industry and for photographic applications as well.

The correct choice is (a) True

For explanation I would say: The above statement is correct. The human body requires several nutrients and minerals in specified QUANTITIES DEPENDING upon several factors LIKE age, gender etc. of the person. Deficiency of magnesium can lead to diabetes.

The correct choice is (c) non-magnetic, non-sparkling

For explanation I would say: Magnesium alloys have a SET of PHYSICAL and chemical properties that DESCRIBE or denote their characteristics. Magnesium alloys are not magnetic nature. Also, UNLIKE some other elements, they are non-sparkling.

Correct answer is (a) True

To ELABORATE: The above statement is correct. Dow’s process is a technique that INVOLVES SEVERAL stages of mixers, thicker, filter, acid mixer, evaporator, shelf DRIER, electrolytic CELL, etc. It is an electrolysis process through which magnesium can be extracted.

Correct ANSWER is (c) limiting

Easy explanation: There are SEVERAL factors to be considered and precautions to be taken while using cutting tools. It is important to limit the friction to PREVENT the generation of heat as that could possibly result in FIRE ACCIDENTS.

Right option is (c) poor

For EXPLANATION I would say: While magnesium is a FAVORABLE element to USE for several purposes, it also has some disadvantages. Magnesium alloys have bad NOTCH sensitivity in fatigue. They also tend to have poor toughness.

Right OPTION is (b) False

Explanation: The above statement is INCORRECT. It is not the most abundantly found ELEMENT on earth. The most abundant metal on earth is aluminium and the most abundant element on PLANET earth is oxygen.

Right choice is (C) improves

To explain: ONE of the advantages of using magnesium in INDUSTRIES is IMPROVED fuel efficiency. Fuel efficiency is a means of thermal efficiency. Fuel efficiency is the conversion of potential energy in fuel into work.

The correct answer is (b) 10%

Explanation: Being able to recycle an element or material is a very advantageous prospect. Materials are recycled based on several FACTORS including time, output, MONEY etc. MAGNESIUM requires only 10% of the energy required to make the primary equipment to be recycled.

Correct option is (a) aluminium, zinc

Easy explanation: Alloying an element with other elements is KNOWN to produce some ADVANTAGEOUS and desired properties that can be used for several INDUSTRIAL and scientific purposes. Magnesium is frequently alloyed with aluminium and zinc.

The correct option is (d) 65%

For explanation I would say: Magnesium is a very BENEFICIAL element to use due to its weight. It is a very lightweight metal and weighs AROUND 65% of aluminium. It does not possess a high amount of STRENGTH but is used when strength is not the PRIMARY factor being CONSIDERED.

Right choice is (b) Carbothermic process

The best EXPLANATION: The carbothermic process of extraction of magnesium is ALSO called as Hansgirg. It is a thermal process that produces magnesium that has a MINIMUM purity of 99.99%. It is one of the SEVERAL PROCESSES available.

Right answer is (b) high blood pressure

To explain I would SAY: The human body requires various NUTRIENTS for nourishment. MAGNESIUM is also NECESSARY for specified quantities. Deficiency of magnesium can result in high blood pressure and AFFECT an individual’s health.

Right ANSWER is (c) MAGNESIUM CALCIUM carbonate

The explanation is: Magnesium can be FOUND commonly in various ores across the world. Dolomite is a magnesium calcium carbonate. Magnesium carbonate is magnesite. Carnallite is magnesium and potassium chloride.

Right option is (c) silvery-white

For explanation I WOULD say: Magnesium is a metal/element that is COMMONLY USED in the aircraft industry due to its advantageous PROPERTIES. It is a silvery-white metal. Lead is a metal that is bluish-grey in colour. Sulphur and chlorine are yellow.

Right choice is (b) False

For explanation: The above STATEMENT is INCORRECT. A large number of products of MAGNESIUM ALLOYS tend to be castings. They can be subjected to several types of treatments and their reaction to heat treatments results in POSITIVE properties.