Introduction To Metallurgy — Part 1 MCQs with Explanations

Let's break down this question step by step to understand how to solve it. First, we need to know what happens when CH₄ (Methane) burns completely . This process is called complete combustion . The chemical reaction for the complete combustion of methane is: CH₄ + O₂ → CO₂ + H₂O This equation isn't balanced yet. We need to make sure the number of atoms of each element is the same on both sides of the arrow. Let's balance it: CH₄ + 2O₂ → CO₂ + 2H₂O This balanced equation tells us that 1 molecule of Methane (CH₄) reacts with 2 molecules of Oxygen (O₂) to produce 1 molecule of Carbon Dioxide (CO₂) and 2 molecules of Water (H₂O). Since the volumes are given at STP (Standard Temperature and Pressure) , a very important principle applies: equal volumes of all gases contain the same number of molecules at STP . This means we can directly use the volume ratios from the balanced chemical equation. So, the balanced equation tells us: 1 volume of CH₄ needs 2 volumes of O₂ . The question states we have 100 m³ of pure CH₄ . Therefore, the amount of Oxygen needed for its complete combustion will be: Oxygen needed = 100 m³ CH₄ * (2 volumes O₂ / 1 volume CH₄) Oxygen needed = 200 m³ O₂ . Now, we need to find out how much air is required to supply this 200 m³ of oxygen. The question tells us that air contains 21 vol.% of oxygen . This means that out of every 100 m³ of air, only 21 m³ is oxygen. We need 200 m³ of oxygen. Let's set up a proportion to find the total volume of air needed: If 21 m³ O₂ is present in 100 m³ Air, Then 1 m³ O₂ is present in (100 / 21) m³ Air. So, 200 m³ O₂ will be present in (100 / 21) * 200 m³ Air. Let's calculate the total air required: Air needed = (200 * 100) / 21 Air needed = 20000 / 21 Air needed ≈ 952.38 m³ Comparing this calculated value with the given options, the closest and correct answer is 952 m³ . Therefore, the correct option is Option D: 952 .

Vacuum Arc Degassing (VAD) is a refining process used after primary steel making to remove dissolved gases and improve steel quality, hence it belongs to secondary steel making . LD process (Basic Oxygen Furnace) converts hot metal into steel by oxidizing impurities and is classified as primary steel making . COREX process produces hot metal directly from iron ore without using coke ovens and sinter plants, therefore it is a direct smelting process. Blast Furnace is used to extract iron from iron ore and is the main process for primary iron making . Thus, the correct matching is P-2, Q-4, R-3, S-1 , which corresponds to Option D .

Turbine blades is the correct answer to “Which of the following are not commercially manufactured by powder metallurgy”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

21 degrees is the correct answer to “Tata salt was tested (FCC) with X-ray (0.071nm) which is diffracted by (110) plane with lattice constant of 0.28nm. Find the diffraction angle for 2 nd order diffraction.”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

rhombohedral is the correct answer to “Which crystal system does not have all axial angles at 90 degrees”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

√3 : 1 is the correct answer to “Two samples A and B of a brittle material have crack lengths in the ratio 3 : 1. The ratio of the tensile strengths (measured normal to the cracks) of A and B will be in the ratio”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

O2 is the correct answer to “Which gas cannot be used to test reactive sample in TGA”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

Q, S is the correct answer to “Transport mechanisms that do not contribute to densification during sintering are: P. Surface diffusion Q. Bulk diffusion R. Bulk diffusion S. Evaporation-condensation T. Viscous flow”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

compacting the powder particles into mechanical and atomic closeness is the correct answer to “In the powde metallurgy processing, the objective of pressing before sintering is to”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

BOF is the correct answer to “A sub-lance is used to monitor composition and temperature in”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

Lead is the correct answer to “X-rays cannot penetrate”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

microwaves is the correct answer to “The waves used by artificial satellites for communication is”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

X-rays is the correct answer to “The structure of solids is investigated by using”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

Polarization technique is the correct answer to “Which one of the following can give information about the corrosion rate”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

9 is the correct answer to “\[\left[ {\begin{array}{*{20}{c}} {21}&0&0 \\ 0&9&0 \\ 0&0&6 \end{array}} \right]MPa\] The maximum shear stress available for the above stress tensor is . . . . . . . . MPa.”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

the volume of the oxide divided by the volume of the metal consumed in oxide formation is the correct answer to “The pilling-Bedworth ratio is defined as”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

$$\frac{{\partial C}}{{\partial T}} = D.\frac{{{\partial ^2}C}}{{\partial {x^2}}}$$ is the correct answer to “Fick's second law of diffusion is stated as:”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

when h, k and l are all odd, or when all are even, (h + k + l) should be divisible by four is the correct answer to “The reflections allowed in DC crystal”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

eyepiece lens is the correct answer to “Which part of a microscope do you look through to see an object magnified”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

U and V is the correct answer to “Identify the combination of mechanisms which best describes sintering of pure metals in powder metallurgy. P. Grain boundary melting Q. Liquid metal freezing R. Interparticle melting S. Recrystallisation T. Grain growth U. Oxidation V. Reduction”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

Gray cast iron is the correct answer to “Which one of the following expands upon solidification”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

P = T(log tr + c) is the correct answer to “The Larson-Miller parameter 'P' connecting the temperature 'T' and the rupture time 't r ' is given as”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

γ-rays is the correct answer to “Which of the following has maximum penetrating power”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

P-2, Q-4, R-1, S-3 is the correct answer to “Match the powder production technique given in Group I with the corresponding shape listed in Group II . Group-I Group-II P. reduction 1. Flaky Q. Gas Atomization 2. Spongy R. Milling 3. Dendritic S. Electrolysis 4. Spherical”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

the speed of sound is the correct answer to “When load is applied to a material, instantaneous strain develops with”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

galvanising is the correct answer to “Coating of zine over steel is known as”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

100yz exp (-t-x2-y2) is the correct answer to “The temperature field od a slab is given by T = 400 - 50z exp (-t-x 2 -y 2 ). The temperature gradient in y-direction is”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

A-2, B-3, C-1, D-4 is the correct answer to “Match the following materials with the method most commonly used for making their powders. A. Nickel 1. Carbothermic reduction B. Tungsten 2. Inert gas atomisation C. Silicon carbide 3. Oxide reduction D. Super alloys 4. Carbonyl process”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

Atomisation is the correct answer to “Alloy powders manufactured by the following process have spherical shapes:”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

two in x-direction, two in y-direction is the correct answer to “The steady state temperature profile of a rectangular sheet of metal inside a furnace can be obtained by solving the following partial differential equation; $$\frac{{{\delta ^2}T}}{{\delta {x^2}}} + \frac{{{\delta ^2}T}}{{\delta {y^2}}} = 0$$ The number of boundary conditions needed to solve this equation are:”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

Q, S is the correct answer to “Cemented carbide cutting tools are P. made by casting Q. made of mainly WC and cobalt R. made of Fe 3 C and cobalt S. made by liquid phase sintering”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

$$\frac{{\sigma \in }}{2}$$ is the correct answer to “The minimum energy required to impose a plastic strain of ε to a metal having unit volume and a constant flow stress = σ is”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

$${C_B} = \frac{m}{{2\sqrt {\pi Dt} }}\exp \left[ { - \frac{{{x^2}}}{{4Dt}}} \right]$$ is the correct answer to “Thin layer of material B (of total amount m) is plated on the end faces of two long rods of material A. These are then joined together on the plated side (see the figure below) and heated to a high temperature. Assuming the diffusion coefficient of B in A is D, the composition profile CB along the rod axis x after a time t is described by”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

6.7 is the correct answer to “An Fe/graphite diffusion couple is annealed at 1273 K. The carbon content (in mass %) on the Fe side of the Fe/graphite diffusion couple will be close to”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

transmitted through the sample is the correct answer to “In TEM electron . . . . . . . . during characterization of sample”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

Solid state diffusion process is the correct answer to “During solid state sintering of powder, the following mechanisms can be active.”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

0.25 is the correct answer to “If σ and ε are true stress and true strain, respectively, the maximum true uniform strain that can be imparted to a material obeying, σ = 1050 ε 0.25 is”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

A-1, B-4, C-2, D-3 is the correct answer to “Match the commonly used manufacturing process for the following products. A. Thoriated nickel wire 1. Single crystal growing B. Aircraft turbine blade made form a nickel based super alloy 2. Sand casting C. Automobile crank shaft made for ductile iron 3. Powder metallurgy D. Silicon wafers used in the electronic in dustry 4. Investment casting”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

MS, MO, MSO4 is the correct answer to “During the roasting of sulfide ore a metal M. the possible solid phased are M. MS. MO and MSO 4 . Assuming that both SO 2 and O 2 are always present in the roaster. The solid phases that can co-exist at thermodynamic equilibrium are”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.

P-2, Q-3, R-4, S-5 is the correct answer to “Match the following. Group 1 Group 2 P. Grain refinement of aluminium 1. Magnesium Q. Improvement of fluidity of cast iron 2. Titanium R. Refinement of graphite flakes in cast iron 3. Phosphorous S. Removal of dissolved hydrogen from molten aluminium 4. Ferro-silicon 5. Chlorine”. This question is standard in competitive examination syllabi for Introduction To Metallurgy.