When heated, calcium carbonate decomposes according to the equation given below: CaCO3 --> CaO + CO2
How many liters of CO2 at STP are produced when 0.68 mol of CaCO3 is heated?

15.2 L
30.4 L
0.679 L
68.0 L

15.2L at STP

Explanation:

Given reaction expression;

         CaCO₃ → CaO + CO₂

Number of moles of CaCO₃  = 0.68mol

Unknown:

Volume of CO₂ produced at STP = ?

Solution:

To solve this problem, we must first find the number of moles CO₂ produced,

     1 mole of CaCO₃ will produce 1 mole of CO₂

   0.68mole of CaCO₃ will produce 0.68mole of CO₂ at STP

Now;

             1 mole of gas occupies a volume of 22.4L at STP;

           0.68mole of CO₂ will then occupy 0.68 x 22.4  = 15.2L at STP

explanation:

metals have excess of electrons whereas non-metals have deficiency of electrons. thus, in order to gain stability metals easily donate their electrons to the non-metals.

for example, electronic configuration of sodium is and electronic configuration of phosphorous is .

when a phosphorous atom and sodium atom combine together then sodium will donate is extra one electron to the phosphorous atom. as a result there will be formation of ionic bond between sodium and phosphorous.

the reaction will be as follows.

there, are three sodium sodium atoms and each of them will donate its one extra electron to phosphorous atom. thus, the sub-shell of phosphorous gets completely filled.  

thus, we can conclude that electrons are transferred from atoms of sodium to atoms of phosphorous. this transfer makes the sodium atoms donate one electron and the phosphorous atoms to gain one electron. as a result, the sodium and phosphorus atoms strongly attract each other.

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health implications of pesticides

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other important considerations

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