Chemical Reactions SNC2D. Changes A change in which no new substances are formed is called a ?

Chemical Chemical ReactionsReactions

SNC2DSNC2D

ChangesChanges

A change in which no new substances A change in which no new substances are formed is called a ?are formed is called a ?

ChangesChanges

A change in which no new substances A change in which no new substances are formed is called a are formed is called a physical physical changechange..

ChangesChanges

A change in which no new substances A change in which no new substances are formed is called a are formed is called a physical physical changechange..

e.g.e.g. ice meltingice melting

(both ice and water (both ice and water

are Hare H22O)O)

ChangesChanges

A change in which new substances are A change in which new substances are formed is called a ?formed is called a ?

ChangesChanges

A change in which new substances are A change in which new substances are formed is called a formed is called a chemical changechemical change or or chemical reactionchemical reaction..

ChangesChanges

A change in which new substances are A change in which new substances are formed is called a formed is called a chemical changechemical change or or chemical reactionchemical reaction..

Signs and SymptomsSigns and Symptoms

Recall the signs that a chemical Recall the signs that a chemical reaction may have occurred:reaction may have occurred:

Signs and SymptomsSigns and Symptoms

Recall the signs that a chemical Recall the signs that a chemical reaction may have occurred:reaction may have occurred:

heat produced or absorbedheat produced or absorbed

Signs and SymptomsSigns and Symptoms

Recall the signs that a chemical Recall the signs that a chemical reaction may have occurred:reaction may have occurred:

heat produced or absorbedheat produced or absorbed light or sound producedlight or sound produced

Signs and SymptomsSigns and Symptoms

Recall the signs that a chemical Recall the signs that a chemical reaction may have occurred:reaction may have occurred:

heat produced or absorbedheat produced or absorbed light or sound producedlight or sound produced colour changecolour change

Signs and SymptomsSigns and Symptoms

Recall the signs that a chemical Recall the signs that a chemical reaction may have occurred:reaction may have occurred:

heat produced or absorbedheat produced or absorbed light or sound producedlight or sound produced colour changecolour change gas producedgas produced

Signs and SymptomsSigns and Symptoms

Recall the signs that a chemical Recall the signs that a chemical reaction may have occurred:reaction may have occurred:

heat produced or absorbedheat produced or absorbed light or sound producedlight or sound produced colour changecolour change gas producedgas produced precipitate formed in solutionprecipitate formed in solution

EquationsEquations

Chemical reactions can be Chemical reactions can be represented by either:represented by either:

EquationsEquations

Chemical reactions can be Chemical reactions can be represented by either:represented by either:

wordword equations using the equations using the namesnames of of the chemicals (e.g. carbon dioxide, the chemicals (e.g. carbon dioxide, water)water)

EquationsEquations

Chemical reactions can be represented Chemical reactions can be represented by either:by either:

wordword equations using the equations using the namesnames of of the chemicals (e.g. carbon dioxide, the chemicals (e.g. carbon dioxide, water)water)

oror chemicalchemical equations using the equations using the

formulasformulas of the chemicals (e.g. CO of the chemicals (e.g. CO22, , HH22O)O)

ReactantsReactants

The substances that are reacting are The substances that are reacting are called ?called ?

ReactantsReactants

The substances that are reacting are The substances that are reacting are called called reactantsreactants and are written on and are written on the the leftleft side of the equation. There side of the equation. There may be only one; if there is more may be only one; if there is more than one, they are separated by ?than one, they are separated by ?

ReactantsReactants

The substances that are reacting are The substances that are reacting are called called reactantsreactants and are written on and are written on the the leftleft side of the equation. There side of the equation. There may be only one; if there is more may be only one; if there is more than one, they are separated by + than one, they are separated by + signs.signs.

ReactantsReactants

The substances that are reacting are The substances that are reacting are called called reactantsreactants and are written on the and are written on the leftleft side of the equation. There may be side of the equation. There may be only one; if there is more than one, they only one; if there is more than one, they are separated by + signs.are separated by + signs.

e.g.e.g.

carbon dioxide + watercarbon dioxide + water

COCO22 + H + H22OO

ProductsProducts

The new substances formed in the The new substances formed in the reaction are called ?reaction are called ?

ProductsProducts

The new substances formed in the The new substances formed in the reaction are called reaction are called products products and and written on the right side of the written on the right side of the equation.equation.

ProductsProducts

The new substances formed in the The new substances formed in the reaction are called reaction are called products products and and written on the written on the rightright side of the side of the equation.equation.

e.g.e.g.

oxygen gas + glucoseoxygen gas + glucose

ProductsProducts

The new substances formed in the The new substances formed in the reaction are called reaction are called products products and and written on the written on the rightright side of the side of the equation.equation.

e.g.e.g.

oxygen gas + glucoseoxygen gas + glucose

OO22 + C + C66HH1212OO66

The two sides of the equation are The two sides of the equation are separated by ?separated by ?

The two sides of the equation are The two sides of the equation are separated by an arrow (pointing separated by an arrow (pointing rightright) that is read as ?) that is read as ?

The two sides of the equation are The two sides of the equation are separated by an arrow (pointing separated by an arrow (pointing rightright) that is read as “produces” or ) that is read as “produces” or “yields.”“yields.”

The two sides of the equation are separated The two sides of the equation are separated by an arrow (pointing by an arrow (pointing rightright) that is read as ) that is read as “produces” or “yields.”“produces” or “yields.”

e.g.e.g.

carbon dioxide + water oxygen gas + carbon dioxide + water oxygen gas + glucoseglucose

COCO22 + H + H22O OO O22 + C + C66HH1212OO66