Question

Q12. State two points of difference between acute and chronic diseases. Write two examples of

each.

Q13. Weight of an object on the surface of Earth is 36N. Calculate:

a) weight of the object on Moon.

b) mass of the object on the surface of Earth

c) mass of the object on the surface of Moon

Q14. Calculate and show which of the following has more number of particles?



100g of iron or 100 g of water (atomic mass of iron = 56u)​

Answer 1

Explanation:

Atomic mass of Na = 23 u

Atomic mass of Fe = 56 u

Then, gram atomic mass of Na = 23 g

Now, 23 g of Na contains = 6.022 x 1023 g number of atoms

Thus, 100 g of Na contains = 6.022 x 1023 / (23 x 100 number of atoms)

100 g of Na contains = 2.6182 x 1024 number of atoms

Then, gram atomic mass of Fe = 56 g

Now, 56 g of Fe contains = 6.022 x 1023 g number of atoms

Thus, 100 g of Fe contains = 6.022 x 1023 / (56 x 100 number of atoms)

100 g of Fe contains = 1.0753 x 1024 number of atoms

Therefore, 100 grams of sodium contains more number of atoms than 100 grams of iron.

Answer 2

Answer:

• Acute diseases occur suddenly.
• Chronic occur over a prolonged period.

_______________________

• Acute last for a shorter period.
• Chronic longer, even for a lifetime.