Atoms and Elements

The smallest part of an element is ________.

• a solution

• an atom

• a compound

• a molecule

Which of the following is not an element ?

• Water

• Hydrogen

• Oxygen

• Carbon

All matter is made of —

• gold

• mixtures

• iron

• atoms

Where are elements displayed, which also indicate their symbols ?

• periods
• Periodic Table
• atoms
• Under the table

Chemists use letters of the alphabet as __________ for the elements.

• numbers

• symbols

• pictures

• none of the above

Dave, Emily, and John are at a jewelry store looking at a diamond necklace. They start discussing the number of protons in a carbon atom, as diamonds are made of carbon. Can you help them with the correct answer? What is the atomic (proton) number?

• 2

• 4

• 6

• 12

An atom with atomic number 10 would have how many protons ?

• 10

• 12
• 3
• cannot be determined 

Substances that cannot be broken down into simpler substances by physical or chemical changes are called (a)   .

Which of the following elements are found before 1669 ? (You can choose multiple answers)

• Sodium

• Arsenic

• Antimony

• Helium

A (a)   property is one which can be observed / measured once the substance undergoes a chemical reaction.