Prep 1 unit 1

What is the number of elements and atoms in ammonia molecule ...... and .......

• Two - Four

• Three - One

• Two - Two

• One - One

It is the smallest part of matter which can exist freely and it has the properties of matter. - It is the building unit of matter.

• Atom

• Molecule

• Element

• Compound

Properties of molecules

• Molecules of matter are in a continuous motion

• There are intermolecular spaces among the molecules of matter

• There are intermolecular forces among the molecules of matter

• All of the previous

Solutions that allow electricity to pass through

• Acidic solutionsn

• alkaline solutions

• some salt solutions

• All of the previous

They react with oxygen very fast, and lose their metallic lustar as sodium and potassium

• Very active metals

• Less active metals

• Inactive metals

• All of the previous

They react with oxygen very fast, but take several days to rust and corrosion as iron

• Very active metals

• Less active metals

• Inactive metals

• All of the previous

It is the simplest pure form of matter which can't be analyzed chemically into simpler form by simple chemical methods

• Atom

• Molecule

• Element

• Compound

What's the symbols of elements

Sodium - Neon - Nitrogen

• Na - N - Ne

• Na - Ne - N

• N - Ne - Na

• Ne - N - Na

 .......... are almost not completely free

• Solid

• Liquid

• Gas

A piece of metal has a mass of 189 gram, volume of 3 cm³ Calculate its density.

• 63 gm/cm3

• 0.015 gm/cm3