Tag: the s-block elements

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Questions Related to the s-block elements

Multiple choice some important compounds of magnesium and calcium the s-block elements chemistry

Formation of super phosphate is:

  1. exothermic reaction

  2. endothermic reaction

  3. reversible reaction

  4. none of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A well powdered phosphate rock or bone ash mixed known quantity of concentrate sulphuric acid is introduced into a cast iron chamber provided with mechanical stirrer and two valves at bottom. Each valve opens in a big chamber called den. The mixture is stirred for 2 to 5 minutes and then dumped mechanically into one of the dens through the valve. The mass is kept in the den for about 24 hours.

${ Ca } _{ 3 }{ \left( P{ O } _{ 4 } \right)  } _{ 2 }+2{ H } _{ 2 }S{ O } _{ 4 }+4{ H } _{ 2 }O\longrightarrow Ca{ ({ H } _{ 2 }P{ O } _{ 4 }) } _{ 2 }+2CaS{ O } _{ 4 }.2{ H } _{ 2 }O+Heat$

A mixture of calcium sulphate and calcium dihydrogen phosphate is obtained .This mixture is called superphosphate.

Multiple choice some important compounds of magnesium and calcium the s-block elements chemistry

Super phosphate consist(s) of:

  1. calcium sulphate

  2. calcium hydrogen phosphate

  3. calcium carbonate
  4. both $A$ and $B$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Single superphosphate (SSP) was the first commercial mineral fertilizer, and it led to the development of the modern plant nutrient industry. This material was once the most commonly used fertilizer, but other phosphorus (P) fertilizers have largely replaced SSP because of its relatively low P content.

The general chemical reaction involved in the production of SSP is

${ Ca } _{ 3 }{ \left( P{ O } _{ 4 } \right)  } _{ 2 }+2{ H } _{ 2 }S{ O } _{ 4 }\longrightarrow Ca{ ({ H } _{ 2 }P{ O } _{ 4 }) } _{ 2 }+2CaS{ O } _{ 4 }$

Multiple choice some important compounds of magnesium and calcium the s-block elements chemistry

Total how many hydrogen atoms are present in one molecule of triple superphosphate?

  1. 6

  2. 8

  3. 9

  4. 12
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Monocalcium phosphate is an inorganic compound with the chemical formula $Ca{ ({ H } _{ 2 }P{ O } _{ 4 }) } _{ 2 }$. It is commonly found as the monohydrate $Ca{ ({ H } _{ 2 }P{ O } _{ 4 }) } _{ 2 }.{ H } _{ 2 }O$ Both salts are colourless solids. They are used mainly as superphosphate fertilizers.

So a total of 6 hydrogen atoms are present.

Multiple choice some important compounds of magnesium and calcium the s-block elements chemistry

Reactants of superphosphate are mixed in a ____________ chamber with a mechanical stirrer and two valves at the bottom. 

  1. cast iron

  2. stainless steel

  3. mild stainless steel

  4. copper
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A well powdered phosphate rock or bone ash mixed known quantity of concentrate sulphuric acid is introduced into a cast iron chamber provided with mechanical stirrer and two valves at bottom. Each valve opens in a big chamber called den. The mixture is stirred for 2 to 5 minutes and then  dumped mechanically into one of the dens through the valve. The mass is kept in the den for about 24 hours.

Multiple choice some important compounds of magnesium and calcium the s-block elements chemistry

Valves of an iron chamber used in the manufacturing of superphosphate opens in a big chamber called _________.

  1. reactor

  2. vessel

  3. den

  4. control room
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A well powdered phosphate rock or bone ash mixed known quantity of concentrate sulphuric acid is introduced into a cast iron chamber provided with mechanical stirrer and two valves at bottom. Each valve opens in a big chamber called den. The mixture is stirred for 2 to 5 minutes and then  dumped mechanically into one of the dens through the valve. The mass is kept in the den for about 24 hours.

Multiple choice some important compounds of magnesium and calcium the s-block elements chemistry

Reactant of the superphosphate production are stirred for ___________ minutes and then into one of the dens through the valve.

  1. 5-10 mins

  2. 10-15 mins

  3. 2-5 mins

  4. 20-30 mins
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A well powdered phosphate rock or bone ash mixed known quantity of concentrate sulphuric acid is introduced into a cast iron chamber provided with mechanical stirrer and two valves at bottom. Each valve opens in a big chamber called den. The mixture is stirred for 2 to 5 minutes and then  dumped mechanically into one of the dens through the valve. The mass is kept in the den for about 24 hours.

Multiple choice some important compounds of magnesium and calcium the s-block elements chemistry

A mixture of single superphosphate and triple superphosphate is called:

  1. mean phosphate

  2. average phosphate

  3. double phosphate

  4. none of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A mixture of single superphosphate and triple superphosphate is called double superphosphate. More than 90% of a typical superphosphate fertilizer is water-soluble.

Hence option C is correct.

Multiple choice some important compounds of magnesium and calcium the s-block elements chemistry

The balanced chemical reaction for the manufacturing of superphosphate is:

  1. $Ca _3(PO _4) _2 +\ 2H _2SO _4 +\ 4H _2O \ \longrightarrow Ca(H _2PO _4) _2 \ + \ 2CaSO _4.2H _2O $
  2. $Ca _3(PO _4) _2 +\ H _2SO _4 +\ 4H _2O \ \longrightarrow Ca(H _2PO _4) _2 \ + \ CaSO _4.2H _2O $
  3. $Ca _3(PO _4) _2 +\ 2H _2SO _4 +\ 2H _2O \ \longrightarrow 2Ca(H _2PO _4) _2 \ + \ CaSO _4.2H _2O $
  4. $Ca _3(PO _4) _2 +\ 4H _2SO _4 +\ 2H _2O \ \longrightarrow Ca(H _2PO _4) _2 \ + \ 2CaSO _4.2H _2O $
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A well powdered phosphate rock or bone ash mixed known quantity of concentrate sulphuric acid is introduced into a cast iron chamber provided with mechanical stirrer and two valves at bottom. Each valve opens in a big chamber called den. The mixture is stirred for 2 to 5 minutes and then dumped mechanically into one of the dens through the valve. The mass is kept in the den for about 24 hours.

${ Ca } _{ 3 }{ \left( P{ O } _{ 4 } \right)  } _{ 2 }+2{ H } _{ 2 }S{ O } _{ 4 }+4{ H } _{ 2 }O\longrightarrow Ca{ ({ H } _{ 2 }P{ O } _{ 4 }) } _{ 2 }+2CaS{ O } _{ 4 }.2{ H } _{ 2 }O+Heat$

A mixture of calcium sulphate and calcium dihydrogen phosphate is obtained .This mixture is called superphosphate.

Multiple choice some important compounds of magnesium and calcium the s-block elements chemistry

What is the chemical formula of triple superphosphate?

  1. $Ca(H _2PO _4).2H _2O$
  2. $Ca{(H _2PO _4)} _2.H _2O$
  3. $Ca(H _2PO _4).3H _2O$
  4. $CaSO _4.3H _2O$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Triple Superphosphate is manufactured in a two stage process. First, sulphuric acid is reacted with phosphate rock, to produce phosphoric acid. Gypsum is a by-product of the stage and is removed. Secondly, the phosphoric acid is reacted with phosphate rock resulting in triple superphosphate.
Calcium superphosphate is an inorganic compound with the chemical formula $Ca{ ({ H } _{ 2 }P{ O } _{ 4 }) } _{ 2 }$. It is commonly found as the monohydrate $Ca{ ({ H } _{ 2 }P{ O } _{ 4 }) } _{ 2 }.{ H } _{ 2 }O$ . Both salts are colourless solids. They are used mainly as superphosphate fertilizers.