Ch 1 Chemical Reactions And Equations Flashcards
What happens when potassium dichromate reacts with hydrogen sulphide??
Elemental sulphur gets deposited
K2cr2o7 + h2so4+h2S gives k2so4 + cr2(so4)3+h2o+S
Why we balance a chemical equation?
To follow the law of conservation of mass
i.e. mass can never be created not be destroyed in a chemical reaction the elements present in the product of the chemical reaction has to be equal to the total mass of the elements present in the reactants.
What Happens when lead nitrate is added with potassium iodide?
It forms lead iodide and potassium nitrate
PbI2(No3)2 + K I gives PbI2(precipitate) +Kno3
Is Respiration endothermic?
No it’s Exothermic
C6H12O6+O2 gives CO2+ H2o + Energy
Which type of reaction is Composting ?
Exothermic
CH4+O2 gives CO2+ H2O+Heat
Which type of reaction is Photosynthesis ?
Endothermic
CO2+H2O plus light gives C6H12O6+ H2O + O2
What happens when calcium carbonate is heated?
It gives Calcium oxide and carbon dioxide
Gives CaO+CO2
AlCl3+NH4OH GIVES??
Al(OH)3+NH4Cl
What is a Chemical reaction?
Process involving a Chemical change in which new substances having new properties are formed from original.
What are the characteristics of chemical reaction?
C G S T P
(FIG OUT ON UR OWN)
How is a thin layer of calcium carbonate formed on wall after applying on it?
Calcium hydroxide reacts with carbon dioxide in air and forms that layer
After 3 days it gives shiney finish
Ca(OH)2 [SLAKED LIME] + CO2 GIVES CaCO3[QUICK LIME] +H2O
What happens when lead nitrate is heated?
Pb(NO3)2 WHEN HEATED GIVES PbO(lead oxide)+4NO2+O2
What happens when ferrous sulphate is heated?
When heated it gives Fe2O3(ferric oxide)+SO2+SO3
What is displacement reaction?
one element takes the place of another element in a compound
A+BC GIVES AC+B
A IS MORE REACTIVE THAN B
What is double displacement reaction?
Exchange of ions b/w 2 compounds to form 2 new compounds
