Understanding Basic Chemistry Concepts

What happens when two hydrogen atoms collide?

• They disappear.

• They stick together to form a molecule.

• They explode.

• They form a new element.

What does the subscript '2' in H2 represent?

• The number of molecules.

• The number of hydrogen atoms in the molecule.

• The number of bonds.

• The number of electrons.

How many bonds can an oxygen atom form?

• Four

• Three

• Two

• One

What is the chemical formula for water?

• H2

• O2H

• HO2

• H2O

How can you identify a compound from its chemical formula?

• It contains only one type of atom.

• It contains different symbols representing different atoms.

• It is written in uppercase letters.

• It has a subscript of 1.

What is the chemical formula for ammonia?

• H3N

• HN3

• NH3

• N3H

How many hydrogen atoms bond with one nitrogen atom to form ammonia?

• One

• Four

• Two

• Three

What is the valency of carbon?

• One

• Two

• Three

• Four

Which gas is commonly known as natural gas?

• Hydrogen

• Methane

• Oxygen

• Ammonia

What is the term for the number of bonds an atom can form?

• Molecular weight

• Electronegativity

• Valency

• Atomic number