The document discusses carbon dioxide (CO2). It provides its molecular formula (CO2), molecular weight (44 amu), and that it occurs in both free and combined states. CO2 is formed through the reaction of limestone and hydrochloric acid. Tests are described that show CO2 extinguishing fires, and reacting with limewater, magnesium ribbons, and other substances. Uses of CO2 include in photosynthesis, fire extinguishers, preserving foods, and manufacturing other chemicals.

1. Mol. Formula = CO2
Mol. Wt. = 44 a.m.u
Occurrence = Free and combined state
Two atoms of oxygen bonded
with one atom of carbon i.e.
covalent bond
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2. Lab Preparation of CO2
• First of all, pieces of limestone are taken in
Wolfe's bottle and dil. HCl is poured from the
thistle funnel.
• When limestone and HCl comes in contact, the
reaction occurs and CO2 gas is formed.
• The formed gas passes through the delivery
tube to the gas jar.
• Since, the gas is heavier than air, it is collected
by upward displacement of air.
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4. Test of CO2
• When carbon dioxide is passed in lime water for a
short time then calcium carbonate is formed.
Ca(OH)2 +CO2 → CaCO3 +H2O
• When carbon dioxide is passed continuously into
lime water for a long time, the milkyness
disappears slowly due to the formation of water
soluble calcium bicarbonate [Ca(HCO3)2].
CaCO3+ Co2 +H20 → Ca(HCO3)2
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5. Test of CO2
• Wet Blue litmus paper turns into red when
inserted in the gas jar
• If a burning matchstick is taken inside the jar, it
will extinguished
• When a burning magnesium ribbon is introduced
into a gas jar filled with carbon dioxide, the
reaction between magnesium and carbon dioxide
takes place. As a result white colored magnesium
oxide is produced along with the formation of
black spots of carbon.
2Mg +CO2 → 2MgO + C
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6. Physical Properties
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7. Chemical Properties
• Reacts with water to form carbonic acid
CO2 + H2O → H2CO3
• Reacts with alkali to from metallic carbonate
CO2 + 2 NaOH → Na2CO3 + H2O
• Reacts with ammonia to form urea
CO2 + 2NH3 → NH2CONH2 + H2O
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8. Uses of CO2
• Green plants use this gas during photosynthesis
process.
• As it non supporter of combustion, it is used in
fire extinguishers.
• It is used in the form of dry ice to preserve fruits,
flesh etc.
• Used in the manufacture of Urea and washing
soda ( Na2CO3 )
• Mixture of O2 and CO2 is called Carbogen which is
used to provide artificial respiration to the
patient of pneumonia
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9. FIRE EXTINGHUISHER
• Carbon dioxide is denser than oxygen. So
when you spray the carbon dioxide on fire, it
sinks under the oxygen, separating the fire
from oxygen. No oxygen, no fire.
• 2NaHCO3+ H2SO4→Na2SO4+ 2CO2+ 2H2O
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10. AMMONIA GAS
• Ammonia (NH3) is an essential compound of
nitrogen and hydrogen.
• Mol. Wt. = 17 a.m.u.
• One atom of Nitrogen and three atoms of
hydrogen bonded with covalent bond
• It is created by the regular decay of vegetable and
animal bodies. The demise and rot of animals
and plants cause the nitrogen compounds exhibit
in them to get deteriorated, producing ammonia.
• Ammonia, likewise, is present in the soil as
ammonium salts.
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11. LAB PREPARATION OF AMMONIA GAS
Liquid NH3
Dry
Hard glass
test tube
Delivery
tube
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12. Lab preparation……
• Ammonia gas is lighter than air, requiring its accumulation by the
downward displacement of air. Since it is quite solvent in water it
can’t be collected by water displacement method.
• Advancing ammonia gas through quicklime (CaO) dries it.
• Being an essential gas, we can’t dry it by advancing it through
concentrated sulphuric acid or phosphorus pentoxide (P2O5). This is
because it reacts with them to frame ammonium sulfate or
ammonium phosphate separately.
• We can’t utilize calcium chloride for drying ammonia gas as it forms
ammoniates with CaCl2
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13. Tests
• The odor of the compound is effectively
perceivable having a trademark pungent
smell.
• It turns wet red litmus blue.
• A glass bar dunked in concentrated HCl when
conveyed near ammonia causes thick white
exhaust of ammonium chloride.
• When added to a solution of copper sulphate,
ammonia turns the solution deep blue
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14. HABER’S PROCESS
• In the industrial sector, ammonia is manufactured at the
Haber's synthesis process.
• In this process, nitrogen and hydrogen are heated in the ratio
of 1:3 in the presence of iron as catalyst and molybdenum as
promoter at temperature of about 500oC, under high
pressure of about 200 - 900 atmospheric pressure.
N2 + 3H2 ↔ 2NH3
• It is essential for production of ammonia at large quantity
because it is a reversible process.
• Since it is reversible, after a certain time product will form the
reactants itself, so less reactant is consumed. Along with that
it is an exothermic reaction, so less heat is required.
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16. Physical Properties
• Ammonia is a gas. It has no color.
• It has a sharp pungent odor having a soapy taste. At
the point when inhaled all of a sudden, it attacks the
eyes bringing tears.
• It is lighter than air.
• It is very soluble in water to form alkali.
• Turns wet red litmus paper to blue i.e. basic in nature
• Latent heat of vaporization is very high which absorbs
heat from the bodies to cool down so used as
refrigerant
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17. CHEMICAL PROPERTIES
• Reacts with water to form ammonium
hydroxide. NH3 + H2O → NH4OH
• Reacts with carbon dioxide to form urea
2NH3 + CO2 → NH2-CO-NH2 + H2O
• Reacts with acids to form respective salts
2NH3 + H2SO4 → (NH4)2SO4
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18. USES
• It is used in the manufacture of chemical
fertilizers.
• It is used as cleansing agent for removing oils
and grease.
• It is used for developing the blue prints for
maps.
• Its solution is used as a laboratory reagent.
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