2017-2018 Cumulative Online Assessment

The chemical symbol for Helium is

• H
• Hg
• He
• O

Sodium is an ingredient in salt.  The chemical symbol for salt is

• N
• Na
• Mg
• S

The chemical symbol for Oxygen is

• Ox
• Og
• O
• On

The chemical symbol for Silicon is

• S
• Sn
• Sc
• Si

The chemical symbol for Carbon is

• C
• Cb
• Ca
• Cn

The two most common elements found in the oceans are.  Remember oceans are made up of water.

• Sodium and Nitrogen
• Oxygen and Aluminum
• Iron and Carbon
• Oxygen and Hydrogen

What is the most abundant element found in the earth's atmosphere?

• Oxygen
• Sulfur
• Nitrogen
• Argon

What element is essential (needed) for all Living Things but is not in the atmosphere?

• Iron (Fe)
• Carbon (C)
• Hydrogen (H)
• Argon (Ar)

Elements are represented by chemical symbol.  Symbols are written with

• all lower case letters
• all capital letters
• always only one  letter
• At least and ONLY one capital letter

The percentage of Nitrogen in the earth's atmosphere is

• one percent
• seventy-eight  percent
• fifty percent
• twenty-one percent