Atoms And Molecules

What is the smallest unit of matter

• Molecule

• Element

• Compound

• Atom

What is a group of atoms bonded together called?

• Element

• Molecule

• Solid

• Liquid

Which of the following is an example of an element?

• O2 (Oxygen)

• H2O ( Water)

• NaCl ( Table salt)

• CO2 ( Carbon Dioxide )

Two atoms in a molecule are joined together with a ______.

Which type of bond is formed when atoms share electrons?

• Ionic bond

• James Bond

• Covalent Bond

Atomic number of an atom = Number of ______

• Neutrons

• Rings

• Protons

• Atomic mass

DNA molecule is made of _____ chains.

• 1

• 2

• 3

• 4

Which of the following is the example of a compound?

• CO2

• H2O

• NaCl

• All of the above

Calculate the atomic mass of an atom is its number of proton = 18 and number of neutrons = 20.

If an atomic number of an atom is 21. The number electrons it has=

• 21

• 42

• 22

• 23