Tag: compounds of s block elements
Questions Related to compounds of s block elements
The reaction of water with slaked lime is studied by ________ .
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putting slaked lime into water taken in a test tube
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putting a lot of water into slaked lime.
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sprinkling a little water on slaked lime.
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none of the above method.
$A \, Ca(HCO _3) _2 + B \, Ca(OH) _2 \to C \, CaCO _3 + D \, H _2O$.
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$A = 1$
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$B = 1$
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$C = 1$
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$D = 2$
$ACa(HCO _3) _2 + BCa(OH) _2 \rightarrow CCaCO _3 + DH _2O$
The function of quick lime mixture is to:
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Absorb moisture present in soda lime
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increase the efficiency of soda lime
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Increase the pH of soda lime
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Take part in reaction with NaOH
$CaO$ is a compound that absorbs moisture easily and rapidly.
Hence option A is the correct answer.
What is the correct order of thermal stability of carbonates of alkaline earth metals?
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$BeCO _3 > MgCO _3 > CaCO _3 > SrCO _3 > BaCO _3$
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$BeCO _3 < MgCO _3 < CaCO _3 < SrCO _3 < BaCO _3$
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$BeCO _3 < MgCO _3 > CaCO _3 > SrCO _3 < BaCO _3$
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$BeCO _3 > MgCO _3 < CaCO _3 < SrCO _3 < BaCO _3$
Correct order of thermal stability of carbonates of alkaline earth metals is
$BeCO _3 < MgCO _3 < CaCO _3 < SrCO _3 < BaCO _3$
Setting of plaster of paris involves:
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oxidation with atmospheric oxygen
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combination with atmospheric $CO _{2}$
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dehydration
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hydration to yield another hydrate
On hydration of Plaster of Paris, converts into Gypsum.
$\underset {\text {Plaster of Paris}}{CaSO _{4} \cdot \dfrac {1}{2} H _{2}O} + \dfrac {3}{2} H _{2}O\rightarrow \underset {Gypsum}{CaSO _{4}\cdot 2H _{2}O}$
The uses of plaster of paris are:
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it is used as plaster for supporting fractured bones
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for making toys and material for decoration
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for making smooth surface
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all of the above
Some of the uses ofplaster of paris are as follows :-
Identify which contributes for strengthening of lime mortar structures and contributes for weakening of RCC structures the factor(s).
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Usage of water containing dissolved salts
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Addition of lime
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Absorption of $CO _2$ from atmospheric air
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Both B and C
Absorption of $CO _{2}$ from atmospheric air contributes for strengthening for lime mortar structure as when atmospheric $CO _{2}$ combines with hydrated lime, limestone is formed which is a solid.
Cement is manufactured from:
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clay
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limestone
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sodium chloride
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both A and B
Two of the raw materials for the manufacture of cement are limestone and clay.
Raw materials used for the manufacture of Portland cement are:
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gypsum and limestone
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limestone and clay
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alumina, clay and gypsum
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gypsum and clay
Limestone and clay are raw materials used in the manufacture of portland cement.
Chemical formula of epsom salt is $CaSO _4.2H _2O$
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True
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False
Magnesium salt is also known as epsom salt. Chemical formula of epsom salt is $MgSO _4.7H _2O$.