Periodic Table and Phase Changes

What is the most abundant element in the Universe?

• Hydrogen

• Helium

• Carbon

• Gold

The Periodic Table of the Elements was first introduced in the 19th century. By whom?

• Abraham Lincoln

• Dmitri Mendeleev

• Albert Einstein

• Marie Curie

What is the atomic number of oxygen?

• O

• 8

• 15.999

Which properties are associated with the group (family) of elements called "Noble Gases", such as helium (He), argon (Ar), neon (Ne) and krypton (Kr)? (multiple selection)

• Gaseous at room temperature and atmospheric pressure

• Inert (non-reactive)

• Extremely reactive

• Liquid at room temperature and atmospheric pressure

H, C, N, O are the symbols of Hydrogen, Carbon, Nitrogen, and Oxygen, respectively. These elements are considered as:

• Metals

• Nonmetals

• Transition Metals

• Alkali Metals

What is the correct way of writing the chemical formula of water?

• H²O

• H₂O

• HO_2

• HO²

How many atoms of each element are present in a molecule of glucose C₆H₁₂O₆?

• 6 atoms of carbon, 12 atoms of hydrogen, and 6 atoms of oxygen

• 6 atoms of carbon, 12 atoms of hydrogen, and 0 atoms of oxygen

• 1 atom of carbon, 2 atoms of hydrogen, and 1 atom of oxygen

Pure substances of carbon exist under various forms in the Universe. Which of the following? (multiple selection)

• Diamond

• Graphite

• Carbon dioxide CO₂

• Fullerene C₆₀

The air we breath is a complex mixture. Which one of the following descriptions is the most accurate?

• 99% of O₂, 1% of other molecules

• 100% CO₂

• 78% of O₂, 21% of N₂, 1% of other molecules

• 78% of N₂, 21% of O₂, 1% of other molecules

What state of matter is pictured?

• Solid

• Liquid

• Gas