Chemical reactions and equations

Cards (27)

  • Why do we store silver chloride in dark-coloured bottles?
    It reacts with light very fast and loses its property by forming chlorine gas and silver. So to avoid this, silver chloride in dark-coloured bottles. 
  • Which of the gases is used to store fat and oil-containing foods for a long time?
    1. Carbon dioxide
    2. b) Oxygen
    3. c) Nitrogen
    4. d) Neon
    nitrogen
  • What are the two chemical compounds used in black and white photography?
    Silver Bromide and Silver Chloride
  • Which statements about the chemical reaction below are incorrect?-
    2PbO(solid) + C(s) →  2Pb(s) + CO2(g)
    (a) Lead is getting reduced
    (b) Carbon Dioxide CO2 is getting oxidised
    (c) Carbon is getting oxidised
    (d) Lead oxide is getting reduced
       (i) (a) and (b)
       (ii) (a) and (c)
       (iii) (a), (b) and (c)
       (iv) all
    option (i) (a) and (b)
  • What is a chemical equation?
    A chemical equation is a representation of chemical reactions through symbols, letters and numbers
  • What is respiration?
    Respiration is the process of burning food in the living body to produce energy. 
  • Respiration - Chemical equation
    C6​H12​O6​+ 6O2​6CO2​ + H2​O + energy (ATP)
  • Types of decomposition reaction?
    Thermal decomposition
    Photolytic decomposition
    electrolytic decomposition
  • The symbol for oxygen is O2.
  • What is combination reaction?
    A reaction in which a single product is formed from two or more reactants is known as combination reaction
  • CaO + H2O --> Ca(OH)2 + Heat
    Complete the reaction
  • Finish the decomposition reaction:
    2FeSO4 --> Fe2O3 + SO2 + SO3
  • Write a reaction for the heating of limestone:
    CaCO3 --> CaO + CO2
  • A compound X present in a dry test tube is heated and produces brown fumes.
    Name compound X and the brown fumes
    Compound X is lead nitrate and the brown fumes are nitrogen dioxide
  • A good example of an exothermic reaction is respiartion
  • A reaction where oxygen is gained or hydrogen is lost, is known as oxidation reaction
  • A reaction where oxygen is lost or hydrogen is gained is known as reduction reaction
  • When both oxidation and reduction take place in a single chemical chemical reaction, it is known as redox reaction
  • Rancidity takes place in fats and oils
  • When fats and oils are left in the open for too long, they become rancid, inedible and produce foul smell. This is known as Rancidity
  • Explain Corrosion
    Corrosion is the phenomenon in which metals deteriorate gradually in the presence of oxygen and air
  • State the prevention methods for rancidity
    Adding antioxidants
    Storing food in airtight containers
    Replacing air by nitrogen
    refrigeration
  • Prevention methods for corrosion
    Galvanization
    electroplating
    painting
  • Why is it advised to clean a magnesium ribbon before burning it?
    Magnesium ribbon reacts with the atmospheric oxygen to form a layer of magnesium oxide which is a stable compound. To prevent further reactions with oxygen, it is therefore necessary to clean a magnesium ribbon before burning it
  • Write a balanced chemical equation:
    Hydrogen + Chloride -- Hydrogen chloride
    H2 + Cl2 -- HCl
  • Barium chloride + aluminium sulphate -- Barium sulphate + Aluminium Chloride
    3BaCl2 + Al(SO4)3 -- 3BaSO4 + 2AlCl3
  • Sodium + water -- Sodium hydroxide + hydrogen
    2Na + 2H2o -- NaOH + H2