Tag: the s-block elements

Questions Related to the s-block elements

What are the two moles of water attached to gypsum called as:

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

  1. water of evaporation

  2. water of condensation

  3. water of hydration

  4. none of these

Show answer
Correct Option: C
Explanation:

The two moles of water attached to gypsum is called as "water of hydration".$CaSO _4.2H _2O$

Formation of super phosphate is:

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

  1. exothermic reaction

  2. endothermic reaction

  3. reversible reaction

  4. none of the above

Show answer
Correct Option: A
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.

Super phosphate consist(s) of:

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

  1. calcium sulphate

  2. calcium hydrogen phosphate

  3. calcium carbonate

  4. both $A$ and $B$

Show answer
Correct Option: D
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

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

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

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

  1. 6

  2. 8

  3. 9

  4. 12

Show answer
Correct Option: A
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.

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

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

  1. cast iron

  2. stainless steel

  3. mild stainless steel

  4. copper

Show answer
Correct Option: A
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.

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

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

  1. reactor

  2. vessel

  3. den

  4. control room

Show answer
Correct Option: C
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.

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

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

  1. 5-10 mins

  2. 10-15 mins

  3. 2-5 mins

  4. 20-30 mins

Show answer
Correct Option: C
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.

A mixture of single superphosphate and triple superphosphate is called:

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

  1. mean phosphate

  2. average phosphate

  3. double phosphate

  4. none of the above

Show answer
Correct Option: C
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.

The balanced chemical reaction for the manufacturing of superphosphate is:

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

  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 $

Show answer
Correct Option: A
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.

What is the chemical formula of triple superphosphate?

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

  1. $Ca(H _2PO _4).2H _2O$

  2. $Ca{(H _2PO _4)} _2.H _2O$

  3. $Ca(H _2PO _4).3H _2O$

  4. $CaSO _4.3H _2O$

Show answer
Correct Option: B
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.