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TRANSCRIPT
Chemical Reactions
SNC2D
Changes
A change in which no new substances are formed is called a ?
Changes
A change in which no new substances are formed is called a physical change.
Changes
A change in which no new substances are formed is called a physical change.
Ex. ice melting
(both ice and water
are H2O)
Changes
Changes that do change the particles (often because the particles are reacting with the particles of another substance) are called chemical changes or chemical reactions.
Changes
Changes that do change the particles (often because the particles are reacting with the particles of another substance) are called chemical changes or chemical reactions.
Changes
Changes that do change the particles (often because the particles are reacting with the particles of another substance) are called chemical changes or chemical reactions.
Ex. Iron reacts with oxygen in the air to create iron (III) oxide (rust).
Signs and Symptoms
Signs that a reaction has occurred include:• Energy produced or absorbed
Signs and Symptoms
Signs that a reaction has occurred include:• Energy produced or absorbed
(light produced, sound produced,
temperature increase
Signs and Symptoms
Signs that a reaction has occurred include:• Energy produced or absorbed
(light produced, sound produced,
temperature increase or decrease)
Signs and Symptoms
Signs that a reaction has occurred include:• Energy produced or absorbed• New product(s) visible
Signs and Symptoms
Signs that a reaction has occurred include:• Energy produced or absorbed• New product(s) visible
(colour change,
Signs and Symptoms
Signs that a reaction has occurred include:• Energy produced or absorbed• New product(s) visible
(colour change, gas produced
Signs and Symptoms
Signs that a reaction has occurred include:• Energy produced or absorbed• New product(s) visible
(colour change, gas produced,
solid precipitate produced)
Equations
Chemical reactions can be represented by either:
• word equations using the names of the chemicals (e.g. carbon dioxide, water)
Equations
Chemical reactions can be represented by either:
• word equations using the names of the chemicals (e.g. carbon dioxide, water)
or• chemical equations using the formulas of the
chemicals (e.g. CO2, H2O)
Equations
The substances that are reacting are called
____?____
Equations
The substances that are reacting are called reactants and are written on the left side of the equation.
Equations
The substances that are reacting are called reactants and are written on the left side of the equation. There may be only one; if there is more than one, they are separated by ?
Equations
The substances that are reacting are called reactants and are written on the left side of the equation. There may be only one; if there is more than one, they are separated by +.
Equations
The substances that are reacting are called reactants and are written on the left side of the equation. There may be only one; if there is more than one, they are separated by +.
Ex.
carbon dioxide + water
CO2 + H2O
Equations
The new substances formed in the reaction are called ___?____
Equations
The new substances formed in the reaction are called products and written on the right side of the equation.
Equations
The new substances formed in the reaction are called products and written on the right side of the equation.
Ex.
oxygen gas + glucose
Equations
The new substances formed in the reaction are called products and written on the right side of the equation.
Ex.
oxygen gas + glucose
O2 + C6H12O6
The two sides of the equation are separated by
___?____
Equations
The two sides of the equation are separated by an arrow (pointing right) that is read as ?
Equations
The two sides of the equation are separated by an arrow (pointing right) that is read as “produces” or “yields.”
Equations
The two sides of the equation are separated by an arrow (pointing right) that is read as “produces” or “yields.”
Ex.
carbon dioxide + water oxygen gas + glucose
CO2 + H2O O2 + C6H12O6
Equations