Science Chemistry Part I

Choose the conductors of electricity?

• Aluminum

• Plastic

• Paper

• Salt water

____________________is not a conductor of thermal energy. It is called an insulator.

• A metal

• Foam

• Copper

• Zinc

The boiling point of a pure substance is a

• physical property

• chemical property

• real property

• a special property

A few physical properties of water are

• clear and odorless

• the boiling point is 100 degrees Celsius

• excellent solvent: you can dissolve many things in it

• it reacts with pure sodium and causes an explosion

Equal amounts of ethanol and water are poured into two beakers and placed on identical heating pads. Which one of them boils first?

• water

• ethanol

• cannot tell

• they boil at the same time

An example of a non metallic substance that conducts electricity

• wood

• graphite or pencil lead

• coal

• salt water

Water is

• a compound

• an atom

• a pure substance

• a compound made from molecules of H2O

Co represents the element Cobalt. Co is

• a mixture of C and o

• a compound made from C and o

• An element with symbol Co in the periodic table

• a pure substance

Cl₂ is the name given to chlorine gas. Chlorine gas is

• an element in the periodic table

• a molecule of two chlorine atoms

• a pure substance

• a compound made of two atoms

Iron is Fe in the periodic table. Oxygen is represented by O in the periodic table and is usually found as a gas O₂ Rust is Fe₂O₃. Rust is a

• pure substance

• compound made of two types of atoms

• molecule made from more than one atom

• new substance that has its own properties.