Available Answers

1. 1.

   Fill in the blank with suitable words:

   1. __________ have definite shape and definite volume.
   2. The molecules in a gas have high __________ energy.
   3. A __________ can be poured from one vessel to another.
   4. __________ exert equal pressure in all directions.
   5. __________ is a homogeneous material made of carbon.
2. 2.

   Differentiate solids, liquids and gases:

   Property	Solids	Liquids	Gases
   Spaces Energy Density Surfaces Molecular motion

3. 3.

   Give one word for the following:

   1. Small particles that make up the matter.
   2. Attractive forces between the molecules of same kind.
   3. Attractive forces between the molecules of different kind.
   4. Substance that takes the shape of its container.
   5. Anything that occupies space and was weight.
   6. Material which has uniform composition and same properties throughout its bulk.
4. 4.

   When 4.2 g of sodium hydrogen carbonate (NaHCO₃) is added to a solution of hydrochloric acid (HCl) weighing 10.0 g, it is observed that 2.2 g of carbon dioxide (CO₂) is released into the atmosphere. The residue left behind is found to weigh 12.0 g. Show that these observations are in agreement with the law of conservation of mass.

5. 5.

   What mass of silver nitrate will react with 5.85 g of sodium chloride to produce 14.35 g of silver chloride and 8.5 g of sodium nitrate if the law of conservation of mass is true?

6. 6.

   4.90 g of potassium chlorate (KClO₃) when heated produced 1.92g of oxygen and the residue (KCl) left behind weighed 2.98 g. Show that these results illustrate the law of conservation of mass.