FPSC MCQs

Electrons carry negative charge.
They occupy regions around the nucleus.

Corrosion involves chemical or electrochemical reactions.
Rusting is a common example involving iron.

Neutrons are electrically neutral.
They are found in atomic nuclei with protons.

Acids donate protons in chemical reactions.
In water, they increase hydrogen-ion concentration.

The proton number is the atomic number.
Changing the proton number creates a different element.

Bases accept protons according to Brønsted-Lowry theory.
Many aqueous bases produce hydroxide ions.

O is the chemical symbol for oxygen.
Element symbols use one or two letters.

pH values below 7 indicate acidity.
A pH of 3 is distinctly acidic.

Iron's symbol Fe comes from the Latin word ferrum.
It is a common structural metal.

pH values above 7 indicate basicity.
A pH of 10 is alkaline.

Sodium's symbol Na comes from the Latin natrium.
It is a highly reactive alkali metal.

Each water molecule has two hydrogen atoms and one oxygen atom.
Its formula is H₂O.