Science and Nature Quiz for 16 July 2025
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Question 1: The six most abundant ions in seawater are chloride (Cl −), sodium (Na +), sulphate (SO4 2−), magnesium (Mg 2+), calcium (Ca 2+), and what?
A
B
Silicon (Si)
Bromine (Br -)
C
Phosphorus (P)
D
Potassium (K +)