Which word below matches with the molecule description?

• A substance made of more than one kind of atom bonded together.

• The tiniest particle of an element that can exist.

• A substance made up of only one type of atom.

• A group of atoms bonded tightly together.

How did Robert Brown know his first explanation about the random movement of particles was wrong?

• He thought the movement was because the pollen grains were alive.

• The water particles are moving randomly, so they can hit the pollen grains from any side at any time.

• Robert Brown saw pollen grains floating on water with a microscope. They jiggled about with no pattern.

• He saw the same type of movement when he looked at flecks of dust in the water, but he knew the dust was not alive.

Identify the element which does not belong to the same group.

• Lithium

• Sodium

• Potassium

• Calcium

In steam, the distance between the molecules is __________ distance between the molecules in liquid water.

Please fill in the blank with the correct answer!

• smaller than

• the same as

• larger than

• not change

Which of the following list of elements are all metals?

• Potassium, calcium, sulfur, argon.

• Lithium, silicon, aluminum, carbon.

• Chlorine, calcium, sodium, neon.

• Sodium, aluminum, beryllium, magnesium.

What is the most common non-metal found in the Earth’s crust?

• silicon

• nitrogen

• oxygen

• hydrogen

Which statement is the true definition of a compound?

• Compounds are the simplest forms of an element.

• Compounds are chemicals that have been melted together.

• A compound is two or more elements chemically combined together.

• A compound is a complicated mixture of chemicals.

The following is the shorthand way to refer to each

element in symbol:

1 Sometimes the symbol is the first letter of the English name of the element.

2 Sometimes the symbol is the first letter of the English name of the element plus another letter from its name.

3 Sometimes the symbol is taken from the name of the element in another language.

4 The first letter of the symbol is always upper case. The second letter, if there is one, is always lower case.

Which of the following element symbol made up of information 3 and 4?

• O

• F

• Na

• Po

An unknown substance decomposes when it is

heated. The unknown substance is most likely to be ______.

• a compound

• an atom

• an element

• an alloy

A Student put a drop of food dye into a glass of water, and the dye spreads throughout the water. Which process occurs?

• Dissolving

• Distillation

• Diffusion

• Derivation