Grade 10 chem test - Nov

Physical properties vs Chemical Properties

Physical Properties	Chemical Properties
Things you can observe or measure without changing the substance. quantative and qualitative properties	Describe how a substance reacts or changes to form something new.
Example: Color, shape, size, mass, volume, melting point, boiling point, density, luster, evaporation	Example: Flammability, ability to rust, reactivity with acid, toxicity, combustion
Testing doesn’t change the substance.	Testing usually changes the substance.

Physical change vs Chemical change

Physical Change	Chemical Change
The substance stays the same, only its appearance or state changes.	A new substance is formed with different properties.
Example: Ice melting into water — it's still water, just a different form.	Example: Iron rusting — iron turns into iron oxide (rust), a new substance.
Usually reversible (you can often get back the original form).	Usually not easily reversible.

Pure substance:

• They are made up of only one kind of particle and have a fixed or constant structure

• Only one type of substance present and cannot be separated into simpler substances by physical means.

• Ex: H₂O, O₂ (no matter how they are  prepared, they will always have this  ratio of atoms)

• They are classified as elements and compounds

Element

• Made of only one type of atom.

• Simplest form of a substance.

• Cannot be broken down into anything simpler by chemical means.

• Ex

  • Oxygen (O₂)

  • Gold (Au) ]

  • Hydrogen (H₂)

  • Iron (Fe)

Compound

• Made of two or more different elements chemically combined in fixed ratios.

• Can be broken down into simpler substances (elements) through chemical reactions.

• Have different properties than the elements that make them.

• Examples:

  • Water (H₂O) — made of hydrogen and oxygen.

  • Carbon Dioxide (CO₂) — made of carbon and oxygen.

  • Salt (NaCl) — made of sodium and chlorine.

Mixture

More than one type of substance present

• can be seperated by filteration 

Heterogenous Mixtures

Can’t see through (mayo, steel, ketchup )

Homogenous

Can see through (Tap water, kool aid)

Isotope

2 or more forms of an element that have the same number of protons but a different number of neutrons. Has unique mass number.

cation

a positive charged ion

anion

negative charged ion

Quantative observation:

measurable or countable, usually involves numbers

Qualitative observation:

describable, not measurable, usually involves adjectives 

• Ex: The triple beam balance has a metallic, reflective surface and a sliding weight system.

Mixtures

More than one type of substance present

Homogeneous or Heterogeneous

What is an Ion?

An ion is a charged atom because it has more or less electrons. This means its number of protons is not equal to its number of electrons .

What is an isotope?

2 or more forms of an element that have the same number of protons but a different number of neutrons.

• They have the same atomic number but a different atomic mass

Each isotope has a unique mass number.

For example:

( Cabon 14)

# of protons : 6

# of neutrons: 8

# of electrons: 6

Property

characteristic that describes a substance

Matter

Anything that has mass and takes up space

Molecule:

Two or more atoms that are chemically combined

Atom:

The smallest particle of an element: a basic unit of matter

Metal

The metal element loses 1 or more of its valence electrons and becomes a cation 

Nonmetal

The nonmetal element gains 1 or more of its valence electrons and becomes an anion 

Alkali metals 

• Group 1 

• very soft and easy to cut through

• very reactive - most reactive metals

• react violently with water and oxygen

• 1 outer shell electron

Alkali earth metals:

• Group 2

• highly reactive but not as much as alkali metals

• gives off bright light when burn in air

• harder/denser

• 2 outer shell electrons

Halogens

• Group 17

• most reactive non-metal

• react with hydrogen to form compounds, which when dissolved in water becomes acid

• 7 outer shell electrons

• not all in gaseaous state

Noble gasses

• odorless, coloourless gasses at room temperature

• Least reactive due to stable electron arrangements

• group 18

Metals (left side of starcase)

• Good conductors of heat and electricity

• shiny, malleable, ductile, lustre

• usually have high densities and high boiling points

• usually in solid state in room temperature

• mercury is the only metal that is liquid

Non metals (right side of staircase)

• Dull, poor conductor, brittle, commonly form negative ions

• fluorine is the most reactive of all elements

• hydrogen is the only non - metal existing on the left side with the metals

Metalloids (along the staircase)

• solids, brittle, semi-conductors

• Ex: boron, silcon, arsenic

5 factors that a chemical change has occured

1. Change in colour

2. Formation of precipate (cloudness will occur due to insoluble solid)

3. A gas is produced or a change in smell is noticed ( if the smell is the same before and agter that is not a change)

4. Change in energy - heat, light or electricity are used or produced

5. It is difficult to reverse (irreversble)

Elements in the same ____ have very similar chemical properties .

group/family

What do elements in the same period have in common?

same number of elctron shells.

Elements in the same horizontal row belong to the same

period

Elements in the same vertical columun in the tsble is called a

group or a family

HCl (aq)

hydrochloric acid

HI (aq)

hydroiodic acid

HF (aq)

hydrofluoric acid

hydrochloric acid

HCl (aq)

hydrofluoric acid

HF (aq)

hydrobromic acid

HBr (aq)

hydroiodic acid

HI (aq)

The stock system and ic and ous system (multivalent metal Ions)

These systems are used when the metal element had more than one possible oxidation number

The stock system

Uses roman numbers indicating the oxidation number of the metal element

Binary compounds/ covalent

compounds consisting 2 nonmetals

Binary compounds/ covalent naming

1. Mono       

2. Di

3. Tri

4. Tetra

5. Penta

6. Hexa

7. Hepta

8. Octa

9. Nona

10. Deca 

The mono prefix is omitted for the first element

In naming covalent/ binary the acceptions are:

NH₃- Ammonia

H₂O- Water

Hydrogen acception for Binary/covalent compound naming

Hydrogen as the first element makes the prefixes omitted.

HCL→ Hydrogen chloride

What are polyatomic Ions?

A group of covalently bonded atoms with an overall charge from gaining or losing electrons.

• Can be seperated by a chemical reaction, not physical

What are binary acids?

Binary acids are composed of two elements, with hydrogen + a nonmetal

Peroxides

More than one oxygen than usual in a compound

Ex: Na₂O_{2 → Sodium peroxide}

H₂O_{2 → Hydrogen peroxide}

when do you use ous

when the charge is lower on a metal that can have multiple charges

when do you use ic

when the charge is higher on a metal that have multiple charges

Fe2 (ic, ous)

Ferrous

Fe3 (ic, ous)

Ferric

Cu (ic, ous)

Cuprous

Cu2 (ic, ous)

Cupric

Sn2 (ic, ous)

Stannous

Sn4 (ic, ous)

Stannic

Pb2 (ic, ous)

Plumbous

Pb4 ( ic, ous)

Plumbic

hydrobromic acid

HBr (aq)

Au³⁺ (ic, ous

Aurric

Au⁺ (Ic, ous)

Aurrous

Oxycides

Taking a polyatomic ion and changing the ending to ic or ous

• if “ate” ending replace with ‘Ic”

• If “ite” ending replace with “ous”

Ex: H⁺  SO₄^2- (sulfate) → H₂SO_4(aq) Sulfuric acid

H⁺  SO₃^2- (sulphite)→ H₂SO_3(aq)Sulfurous acid

A compound that is formed from a metal and a

non-metal is likely a(n)

Ionic

Two atoms can join together by sharing

electrons in a(n)

Molecular/covalent

The substances that are formed during a

chemical reaction are called the

product

The starting materials in a chemical reaction are

called the

reactant