Name: ______Block: ______
Structure and Transformation of Matter Review Sheet
Properties of Matter & Changes:
- Physical properties: properties that can observed _without chemically changing the substanceExamples:_color, density, melting point, etc._____
- Physical change: A change to a substance that does not change the chemical identity (can be reversed)
- Chemical properties: _Can only be observed by chemically changing the substance and creating a new substance___Examples:_flammability, reacting, etc______
- Chemical change: A change to a substance that changes its chemical identity and creates a new substance
Periodic Table of Elements:
- Arranged in order by _atomic number
- Columns have similar _properties (ex: elements in Group 1 all very reactive)
- 11 is the atomic number
- 23.0 is the atomic mass
- The chemical symbol is Na
- The chemical name is Sodium
- All living things are made up mostly of these 4 elements: C (carbon), H (hydrogen), O (oxygen), N (nitrogen)
Element, Compound or Mixture:
__Element___: pure substance made up of one kind of atom; found on periodic table.
__Compound_: Made up of two or more elements that are chemically combined.
___Mixture___ : Two or elements or compounds that are not chemically combined.
Write E, C or M if it is an element, compound or mixture:
H2O - CTrail Mix - MSalt water - MHe - ECopper - E
Hydrogen - ENaOH - COil & water - MKool Aid - MHCl - C
Carbon -EHg - ESugar water - MAluminum - ENaCl - C
Chemical Reactions:
Chemical reactions involve two main kinds of change:
- Formation of a newsubstance
Examples:
- Gas bubbles when sodium carbonate and hydrochloric acid are combined
- Solid formed when two liquids (copper sulfate solution and sodium carbonate solution) are combined. This is called a _precipitate
- Changes in __energy_
Example:
- Heating/burning sugar over a candle flame
- __Endothermic_ heat is taken in (like the sugar/candle)
- __Exothermic_ heat is given off (like the fireworks)
The rate (speed) of a chemical reaction can be affected four factors:
- Increasing __temperature__ will increase the rate of the reaction because the particles are moving faster.
- Increasing _surfacearea___ will increase the rate of the reaction because more “edges” are interacting and therefore reacting.
- Increasing the _concentration_ will increase the rate of the reaction because there are more particles in the same amount of space.
- Using a __catalyst_will increase the rate of the reaction, even though it is not actually part of the reaction.
Chemical Equations:
What is a chemical equation? _A short way to show what happens in a chemical reaction
_Reactants_: are the substances that react in a chemical reaction
_Products_ : are the substance produced in a chemical reaction
C + O2 → CO2 CH4 + 2O2→ CO2 + H2O
Which numbers are coefficients? Which numbers are coefficients?
Big #’s in front (1’s in this case)1’s and 2
Which numbers are subscripts? Which numbers are subscripts?
Little #’s below (2’s in this case)4, 2, 2, 2
Is this equation balanced? yesIs this equation balanced?No
Balance and rewrite the equation. Balance and rewrite the equation.
CH4 + 2O2→ CO2 + 2H2O