PART - 1 CH - 1 Chemical Reactions and Equations — Science STD 10 — Question

What is the minimum number of rays required for locating the image formed by a concave mirror?

How do we know that two different individual organisms belong to to the same species?

Name the major chemical properties (reactions) of carbon compounds.

State the name of enzyme involved in digestion of protein and its location.

What is a source of energy?

Why is charcoal used as a fuel?

Mr Bharat's 65 year old mother was complaining about blurred vision in both the eyes due to which she could not see things clearly. Mr Bharat took his mother to an eye hospital. The doctor examined her eyes carefully and concluded that she has a medical condition which could not be corrected by using any type of spectacle lenses and it required surgery. Her eyes were operated upon and she could then see once again properly.
(1) What could be the defect in the eyes of Mr Bharat's mother?
(2) What happens to the eye lens during this defect? What is done during surgical operation of the eyes to restore the correct vision?
(3) What values do you learn from Mr Bharat in this episode?

Give structural formulae of the compounds using their IUPAC names:
Benzene