1. Compound Chemical formula Elements present Quick lime CaO Calcium, oxygen Hydrogen bromide HBr Hydrogen, bromine Baking powder NaHCO3 Sodium, hydrogen, carbon, oxygen Potassium sulphate K2SO4 Potassium, sulphur, oxygen For more answers visit to website: https://www.tiwariacademy.com/ncert-solutions/Read more

    Compound Chemical formula Elements present
    Quick lime CaO Calcium, oxygen
    Hydrogen bromide HBr Hydrogen, bromine
    Baking powder NaHCO3 Sodium, hydrogen, carbon, oxygen
    Potassium sulphate K2SO4 Potassium, sulphur, oxygen

    For more answers visit to website:
    https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-3/

    See less
    • 0
  2. (a) Magnesium chloride →MgCl2 (b) Calcium oxide →CaO (c) Copper nitrate →Cu(NO3)2 (d) Aluminium chloride →AlCl3 (e) Calcium carbonate →CaCO3 For more answers visit to website: https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-3/

    (a) Magnesium chloride →MgCl2
    (b) Calcium oxide →CaO
    (c) Copper nitrate →Cu(NO3)2
    (d) Aluminium chloride →AlCl3
    (e) Calcium carbonate →CaCO3

    For more answers visit to website:
    https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-3/

    See less
    • 0
  3. A polyatomic ion is a group of atoms carrying a charge (positive or negative). For example, ammonium ion (𝑁𝐻+/4), hydroxide ion (OH−), carbonate ion (𝐶𝑂2/3−), sulphateion (𝑆𝑂2/4−). For more answers visit to website: https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-3/

    A polyatomic ion is a group of atoms carrying a charge (positive or negative). For example, ammonium ion (𝑁𝐻+/4), hydroxide ion (OH−), carbonate ion (𝐶𝑂2/3−), sulphateion (𝑆𝑂2/4−).

    For more answers visit to website:
    https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-3/

    See less
    • 1
  4. Carbon + Oxygen → Carbon dioxide 3g of carbon reacts with 8 g of oxygen to produce 11g of carbon dioxide. If 3g of carbon is burnt in 50g of oxygen, then 3g of carbon will react with 8 g of oxygen. The remaining 42 g of oxygen will be left un-reactive. In this case also, only 11g of carbon dioxide wRead more

    Carbon + Oxygen → Carbon dioxide
    3g of carbon reacts with 8 g of oxygen to produce 11g of carbon dioxide. If 3g of carbon is burnt in 50g of oxygen, then 3g of carbon will react with 8 g of oxygen. The remaining 42 g of oxygen will be left un-reactive. In this case also, only 11g of carbon dioxide will be formed. The above answer is governed by the law of constant proportions.

    For more answers visit to website:
    https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-3/

    See less
    • 0
  5. Mass of boron = 0.096g (Given) Mass of oxygen = 0.144g (Given) Mass of sample = 0.24g (Given) Thus, percentage of boron by weight in the compound = 0.096×1000. / 24% = 40% Thus, percentage of oxygen by weight in the compound = 0.144×1000./24% = 60 % For more answers visit to website: https://www.tiwRead more

    Mass of boron = 0.096g (Given)
    Mass of oxygen = 0.144g (Given)
    Mass of sample = 0.24g (Given)
    Thus, percentage of boron by weight in the compound = 0.096×1000. / 24% = 40%
    Thus, percentage of oxygen by weight in the compound = 0.144×1000./24%
    = 60 %

    For more answers visit to website:
    https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-3/

    See less
    • 0