A substance of two or more different atoms is?

• a neutrino.

• an isotope.

• a chemical compound.

An atom with 5 electrons in its outer shell is?

• trivalent.

• Monovalent

•  Bivalent

The heat required to change a liquid to a gas at constant temperature is the heat of.

•  fusion.

• condensation.

• vaporisation

What is the number of electrons in the inner-most shell of an atom?

• 4

• 8

• 2

What does an oxygen atom consist of?.

• Protons, neutrons and electrons.

•  Protons and electrons.

• Protons and neutrons.

The maximum number of electrons in the second shell is.

• 4.

• 8.

• 2.

There are solids, liquids and gases present in the universe and every unit of theirs occupy some space. This is called.

• matter

• compound

• mass

Change from solid to gas state without going through liquid state is called.

• transformation

• sublimation

• state leap.

What is the smallest particle of matter that can exist in nature?.

• A molecule.

• An isotope.

• An atom.

An atom with 3 free electrons in its outer shell is said to be?

• pentavalent

• covalent

• trivalent