Which of the following best defines an element?

• A substance made of two or more different atoms bonded together

• A substance that can be separated into parts by physical methods

• A primary constituent of matter that cannot be chemically broken down

• A substance that has a variable composition

What is a compound?

• A substance containing only one type of atom

• A substance that contains more than one element or compound not in a fixed ratio

• A substance that can be broken down by physical means

• A substance consisting of atoms of different elements chemically bonded in a fixed ratio

What is a pure substance?

• A mixture that can be separated easily

• A substance made of only one type of particle with a fixed composition

• A combination of two or more substances mixed together

• A substance that changes composition over time

Chemistry is the study of the ______________ and properties of matter.

How are the particles arranged in a solid?

• Far apart and move freely

• Close together and vibrate in fixed positions

• Close together but move past each other

• Spread out with no regular pattern

How are the particles arranged in a liquid?

• Close together but move past each other

• Far apart and move quickly in all directions

• Fixed in place and cannot move
  

• Spread out evenly with no motion

How are the particles arranged in a gas?

• Close together and vibrate in place

• Close together but slide past each other

• Far apart and move freely in all directions

• Arranged in a rigid, repeating pattern

What is the chemical symbol for Lead?

• Pb

• Le

• Ld

• Au

A mixture where the components are uniformly distributed, like salt dissolved in water, is called:

• A pure substance

• A homogeneous mixture

• A heterogeneous mixture

• A compound

What is a heterogeneous mixture?

• A mixture where the components are evenly distributed and cannot be easily separated

• A mixture where the components are not evenly distributed and can usually be seen separately

• A mixture that is made of only one substance

• A pure substance with fixed composition