Miscellaneous Material MCQ Quiz in मराठी - Objective Question with Answer for Miscellaneous Material - मोफत PDF डाउनलोड करा

Granite:

1. Granite is unstratified rock, igneous rock, silicious rock, intrusive rock.
2. Granite is hard, coarse-grained rocks of crystalline structure.
3. It is a type of igneous rocks (plutonic rocks).
4. Granites can be predominantly white, pink, or grey in colour, depending on their mineralogy.
5. These rocks mainly consist of feldspar, quartz, mica, and amphibole minerals.
6. It contains 20% and 60% quartz by volume, and at least 35% of the total feldspar.

Important Points

Classification of rock: 

Geological Classification	Physical Classification	Chemical Classification
This Classification is done on the basis of their Geological Formation.	This Classification is done on the basis of their physical structural formation.	This Classification is done on the basis of their chemical composition.
Sedimentary rocks Igneous rocks Metamorphic rocks	Stratified rocks Unstratified rocks Foliated rocks	Argillaceous rocks Calcareous rocks Siliceous rocks

Explanation:

Hardness is measured by scratching the mineral with series of substances of known variation in hardness using Mohs scale.

Hardness Number for different minerals based on Mohs scale are:

Mineral	Scale Number
Talc	1
Gypsum	2
Calcite	3
Fluorite	4
Apatite	5
Feldspar	6
Quartz	7
Topaz	8
Corundum	9
Diamond	10

Quick lime:

The lime which is obtained by the calcination of comparatively pure lime stone is known as the quick lime or caustic lime. It is capable of slaking with water and has no affinity for carbonic acid.

Its chemical composition is CaO i.e. oxide of calcium and it has great affinity for moisture.

Slaked lime:

The product obtained by slaking of quick lime is known as the slaked lime or hydrate of lime. It is in the form of white powder and its chemical composition is Ca(OH)₂ or hydrated oxide of calcium.

Slaking:

When water is added to the quick lime in sufficient quantity a chemical reaction takes place. Due to this chemical reaction the quick lime cracks, swell and falls into a powder form which is the calcium hydrate Ca(OH)₂ and it is known as the hydrated lime. This process is known as the slaking.

Explanation:

Sedimentary rocks:

Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at the Earth's surface, followed by cementation. Typical sedimentary rocks are sandstone, limestone, Laterite, shale, Gypsum etc. 

Metamorphic rocks:

These are formed by the change in character of the pre-existing rocks when subjected to great heat and pressure. This process is known as metamorphism. Examples are Gneiss, schist, Marble, Slate etc. 

Important Points

Rocks	Classification	Rocks after Metamorphism
Granite	Igneous rock	Gneiss
Basalt	Igneous rock	Schiest
Limestone	Sedimentary rock	Marble
Mudstone	Sedimentary rock	Slate
Sandstone	Sedimentary rock	Quartzite

Concepts:

Crystallization test of stone is performed to determine durability in which a specimen of 50 mm diameter and 50 mm height is dipped into sodium sulphate for 16 to 18 hours at room temperature (20⁰ to 30⁰ C). The specimens are then taken out of the solution and kept in air for 4 hours. They are then oven dried at a temperature of 105⁰ C for 24 hours and then cooled at room temperature. This process is repeated for 30 cycles and weighed after that. The change in weight indicates the decay of stone.

Change in weight of stone = W₁ – W₂

Where

W₁ is the original weight of specimen

W₂ Weight of specimen after 30 cycles of test

Other tests on Stone:

1. Brard's Test -  This is done to check for frost resistance. A few small pieces of freshly quarried stone are immersed in a boiling solution of soda sulphate (Glauber's salt) and are weighed. These are then removed and kept suspended for few days and weighed again. The loss in weight indicates the probable effect of frost.

2. Acid Test –This is done to check weather resistance and confirm the power of stones to withstand  atmospheric conditions. 100 g of stone chips are kept in a 5 per cent solution of Sulfuric acid or HCI for 3 days. Then the chips are taken out and dried. The sharp and firm corners and edges are indication of sound stone.  

Explanation:

Various Test for Testing of tiles are:

i) Moisture Expansion Test

ii) Water Absorption Test

iii) Bond Strength Test

iv) Transverse Strength Test

v) Impact Test

vi) Thermal Shock Resistance Test

vii) Breaking Strength test

viii) Chemical Resistance Test

ix) Modulus of Rupture Test

x) Surface Abrasion Test

xi) Hardness Test

Hence, all the given test is required for the testing of tiles. The answer will be D.

Explanation:

Different types of lime:

Fat lime/stone lime/rich lime:

(i) This lime slakes vigorously due to which its volume increases by 2 to 2.5 times than its original volume. Hence it is referred to as fat lime.

(ii) It posses a perfectly white color, hence also termed as white lime.

(iii) It is obtained by the calcination of limestone of approx. 95% purity, hence it is also referred to as pure lime, rich lime, or highly caustic lime.

(iv) Its properties are:

• It hardness very slowly with vigorous slaking.
• It has good solubility in water
• It possesses a high degree of plasticity.
• In the presence of air, it sets slowly.
• Fat lime is mostly used for plastering and whitewashing.​

​Additional InformationHydraulic lime:

(i) It is also referred to as water lime as it is capable of setting in water and in damp locations.

(ii) It is obtained by the calcination of limestone having the purity in the range of 70 - 92%.

(iii) It is insoluble in water and possesses off-white colour.

(iv) Its hardness is comparatively faster than fat lime, hence is used in engineering works where strength is required. Ex: Brick masonry and stone masonry.

Poor lime:

(i) It is also referred to as impure lime or lean lime as it is obtained from the calcination of limestone having a purity of less than 70%.

(ii) This lime does not undergo slaking, hardness very slowly, possess muddy white colour, hence is used in Engineering works of minor importance. Ex: Brickwork around the foundation. 

Explanation:

A cement concrete layer in the proportion 1: 2: 4 is generally provided at the plinth level to work as a damp-proofing course. The depth of the cement concrete layer varies from 40 mm to 150 mm. It stops the rise of water by capillary action and it is found to be effective at places where the damp is not excessive.

Estimation of D.P.C work is performed/measured in square meters of area.

Materials widely used for damp proofing other than concrete include:

1. Flexible materials like butyl rubber, hot bitumen (asphalt), plastic sheets, bituminous felts, sheets of lead, copper, etc.
2. Semi-rigid materials like mastic asphalt. 

Explanation:

Different types of lime:

Fat lime:

(i) This lime slakes vigorously due to which its volume increases by 2 to 2.5 times than its original volume. Hence it is referred to as fat lime.

(ii) It posses a perfectly white colour, hence also termed as white lime.

(iii) It is obtained by the calcination of limestone of approx. 95% purity, hence it is also referred to as pure lime, rich lime, or highly caustic lime.

(iv) Its properties are:

• It hardness very slowly with vigorous slaking.
• It has good solubility in water
• It possesses a high degree of plasticity.
• In the presence of air, it sets slowly.
• Fat lime is mostly used for plastering and whitewashing.

Hydraulic lime:

(i) It is also referred to as water lime as it is capable of setting in water and in damp locations.

(ii) It is obtained by the calcination of limestone having the purity in the range of 70 - 92%.

(iii) It is insoluble in water and possesses off-white colour.

(iv) Its hardness is comparatively faster than fat lime, hence is used in engineering works where strength is required. Ex: Brick masonry and stone masonry.

Poor lime:

(i) It is also referred to as impure lime or lean lime as it is obtained from the calcination of limestone having a purity of less than 70%.

(ii) This lime does not undergo slaking, hardness very slowly, possess muddy white colour, hence is used in Engineering works of minor importance. Ex: Brickwork around the foundation. 

Explanation:

Asbestos:

• It occurs in nature mostly in form of veins among rock of specific composition, asbestos minerals are fibrous in structure and splits into fine fibers under mechanical force. 

• Asbestos is held together in one direction, whereas the lateral bond with the adjacent molecules is quite weak, due to which it has high tensile strength long the fiber only.
• Asbestos has good absorption capacity and when mixed  with portland cement and wetted by water, it absorbs ie retains firmly to the surface, therefore asbestos cement is also considered finely reinforced cement stone
• Asbestos has low heat and electrical conductivity, high resistance to alkali and poor resistance to acids. The quality of asbestos cement items depends greatly on that of asbestos and on fineness of cement.
• Natural asbestos are subdivided into 2 forms:

1. Acid-resistant
2. Non acid resistant

Use of asbestos:

1. Used to make AC sheet and boards for roofing, false ceiling, partitions, and window panes
2. In form of pipe it is used to drain water
3. It is also used for making paints