Define valency and radical. State two differences between a lunar and solar eclipse. Name the elements in ammonia, common salt, and water. List three agents of pollination.

here are the answers to the questions from the image:

8. Define the following terms:

   • (i) Valency: Valency is the combining power of an element, representing the number of hydrogen atoms that an atom of the element can combine with or displace.
   • (ii) Radical: A radical is a group of atoms that behaves as a single unit and carries a charge, acting like a single atom in chemical reactions.

   State two differences between eclipse of the moon and eclipse of the sun.

   • (i) An eclipse of the moon (lunar eclipse) occurs when the Earth passes between the Sun and the Moon, casting a shadow on the Moon. An eclipse of the sun (solar eclipse) occurs when the Moon passes between the Sun and the Earth, casting a shadow on the Earth.
   • (ii) A lunar eclipse can be seen from anywhere on the night side of Earth, while a solar eclipse is only visible from a relatively small area on Earth.

   a) Name the elements that make up the following compounds:

   • (i) Ammonia: Nitrogen, Hydrogen
   • (ii) Common Salt: Sodium, Chlorine
   • (iii) Water: Hydrogen, Oxygen

   b) (i) List three agents of pollination.

   • 1. Wind
   • 2. Insects (e.g., bees, butterflies)
   • 3. Water