Chapter 5 - Elements Flashcards Preview

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Flashcards in Chapter 5 - Elements Deck (24)
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What is the Atomic Theory?

• All matter is made of small, indivisible particles called atoms
• All the atoms of an element are identical in properties such as size and mass
• Atoms of different elements have different properties
• Atoms of different elements can combine in specific ways to form new substances


What is a Bohr model or Bohr diagram?

A diagram that shows the nucleus, and the orbiting electrons.
Also includes indications such as “2p 2n” on the nucleus area.

The most inner orbit has up to 2 electrons,
The other orbits are all up to 8.

*in pairs*


What are the symbols of protons, neutrons, and electrons?

What are their relative masses?

p, n, e

Relative mass:
Proton 1836
Neutron 1837
Electron 1

Proton 1 amu
Neutron 1 amu
Electron Neglible

amu = atomic mass unit


Name some physical properties for metals.

Metals are mostly shiny, and silver or grey. They are good conductors of electricity and heat. Malleable and ductile.


Non-Metals vary in properties. What are some non-metal solids?


Does not comply with properties of metal and is reactive and will burn in air to produce a poisonous gas.


What is the most common metalloid?

The most common metalloid is silicon.


iron (Fe) + carbon (C) = ?

iron (Fe) + carbon (C) = STEEL

Steel is fairly resistant to corrosion.


List some properties of iron (Fe).

Plain iron corrodes easily in moist air.
Silver-grey, can be molded and shaped when heated.
Hard enough to keep a sharp edge.


List some properties of carbon (C).

Graphite and diamond are both forms of carbon.
Your body and the food you eat contain many different carbon compounds.


List some properties of hydrogen (H).

Hydrogen is the most common element in the universe.
Lightest and simplest of all atoms.
On earth, almost all of the hydrogen that is present is in water.
Pure hydrogen is colourless, odourless, and lighter than air.
Extremely FLAMMABLE.


List some properties of oxygen (O).

21% of the air we breathe.
Oxygen gas; ozone (toxic to breathe).
Most common element on earth’s surface.
Makes up more than 50% in rocks, combining with silicon (both are a major part of glass).


List some properties of sodium (Na).

Conducts electricity, is shiny, silver-grey, malleable, and ductile.
Sodium metal burns in air.
Soft, melting point of 98°C.

Pure sodium metal is usually stored in oil.


List some properties of chlorine (Cl).

Yellow-green gas at room temperature.
High concentrations of chlorine gas are focus and destroys lung tissue quickly.

Used at lower concentrations as a disinfectant.


What is the atomic number? (Smaller number)

Atom number is the number of protons in an atom of an element.


What is atomic mass? (Larger number)

Atomic mass = protons + neutrons

*measured in amu*


What is an ion?

An ion is an atom or group of atoms that has lost or gained electrons.



Period - horizontal
Group/chemical family - vertical


List the similarities in alkali metals.

Silver-grey, malleable and ductile, and conduct electricity and heat.
LOW melting points.
React easily with water and air.


List the similarities in halogens.

Noticeable colours!
Bromine (liquid) and iodine (solid) at room temperature turn into gases with slight heating, like other halogens.
Very reactive.
Chlorine, bromine, and iodine can all be used as disinfectants.


List the similarities in noble gases.

All exist naturally as colourless gases.
Will glow with bright colours if an electric current is passed through them, as in a neon light.

NONE of these gases is chemically reactive e cost in certain special situations.


What is another name for shells? (Orbit outside the nucleus)

Another name for shells is energy levels.


Group 1 (Alkali metals) have what in common because of their similar valence electron arrangements?

They can all form ions with a 1+ charge.


Group 18 (noble gases) have what in common because of their similar valence arrangements?

They all have filled valence shells, so they are not very reactive.


What are isotopes?

Isotopes are two or more forms of an element with the same # of protons and different # of neutrons.