The relative abundance of dissolved salts in seawater in descending order is as follows

A. chlorine, sodium, sulphate, magnesium, calcium, potassium
B. sodium, chlorine, magnesium, potassium, sulphate, calcium
C. chlorine, magnesium, calcium, sodium, potassium, sulphate
D. chlorine, sodium, magnesium, calcium, potassium, sulphate
✅ The correct answer is option A.

Oxygen was independently discovered by

A. Rutherford
B. William Ramsay
C. Joseph Priestley
D. Neils Bohr
✅ The correct answer is option C.
Oxygen was independently discovered by Carl Wilhelm Scheele, in Uppsala, in 1773 or earlier, and Joseph Priestley in Wiltshire, in 1774, but Priestley is often given priority because his work was published first.