Human Eye and Colourful World — Science STD 10 — Question

How does the electropositive character of elements change on going down in a group of the periodic table?

Name the bacteria whose presence in water indicates the contamination with disease-causing micro-organisms.

Name the rule that gives the direction of force on a current carrying conductor placed perpendicular to the magnetic field.

What are the four blood groups in humans?

Apart from cattle dung, what other substances can be added to a biogas plant?

What is the range of temperature which can be achieved in a box-type solar cooker in two to three hours?

Name the gland which controls the secretion of hormones from the pituitary.

An element X which has 6 electrons in its outermost shell, require 2 electrons to complete its octet for attaining noble gas configuration. X is an essential element for the survival of all living beings. What is X?

Name two metals which are found in nature in the free state.

Name an alloy of lead and tin.