Physical and Chemical Change

Physical and Chemical Change

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Multiple Choice

What is this paper?

• Element

• Molecule

• Compound

• Mixture

• Paper is a compound made up of Carbon, Hydrogen and Oxygen

• C₆H₁₀O₅

Open Ended

What are some characteristics of this sheet of paper?

• White

• Flat

• Square

• It is a solid

• It has a low density

• It is thin

Because we do not have to change the CHEMICAL makeup of the paper to observe these properties they are termed PHYSICAL Properties

Multiple Choice

Physical Properties are

• properties that can only be observed by the eyes

• properties that can only be measured

• properties that describe how a substance changes into a completely new substance

• properties that can be observed without changing the identity of the substance

Examples of Physical Properties

• Mass

• Density : Mass/ Volume

• Color

• Elasticity : Ability to stretch

• Ductility : Ability to be made into wires

• Malleability : The ability to change shape

• Transparency and Opaque

Multiple Choice

An example of a physical property is

• the ability to rust

• flammability

• acidity

• color

Multiple Choice

Which of these is a physical property?

• color

• weight

• volume

• all of the above

Multiple Choice

Mass, relative density, solubility, color, texture, state of matter, conductivity, etc.

• Physical state

• Insulators

• Physical Properties 

• Inferences

Multiple Choice

A characteristic that can be observed or measured such as color, state, or hardness is referred to as a...

• Physical property

• Chemical property

• Physical change

• Chemical change

Open Ended

Give an example of a Physical Property

Fill in the Blank

Because we do not have to change the chemical makeup of the paper to observe these properties they are termed ________________Properties

Open Ended

Do you believe that the chemical makeup of the paper will change if torn into pieces?

Since the paper chemical makeup has not been altered means it has gone through a Physical Change

A Physical change is one where the appearance of the substance is altered but the chemical makeup of the substance does not change

Examples of Physical Changes

• Ice melting , freezing (Phase Change)

• Crushing a can

• Boiling Water

• Mixing salt and water

• Glass Breaking

​​Breaking Glass
Still glass just smaller pieces

Shredding paper
Still paper just smaller pieces

Melting Ice
Still water just in a different state ( Liquid)

​​Evaporation
Still water just in a diferent state ( Gas)

Multiple Choice

A physical change is

• a change where the characteristics do not change the substance

• a change where the characteristics do change the substance

• a change where the chemistry changes

Multiple Choice

In physical change , the substance formed has different properties than the original substance.

• True

• False

Multiple Choice

Which of the following is a example of physical change ?

• burning of wood

• photosynthesis

• melting of ice-cream

• ripening of fruit

Multiple Choice

Chemical or Physical? Glass breaking into tiny shards

• Chemical Change

• Physical Change

Multiple Choice

Any change in the state of matter of a substance is a...

• Physical Change

• Chemical Change

Multiple Choice

A change that alters the physical properties of a substance without changing its composition.

• Physical Change

• Chemical Change

Multiple Choice

Evidence of a physical change.

• New substance

• Shape Change

• Light produced

• Gas released.

Open Ended

Give an example of a Physical Change

Open Ended

Do you believe this piece of paper can be burnt?

Open Ended

Did the elements in the paper change by burning it? Can it be returned to its former state ,Why? or Why Not?

When the paper was burned it turned to ash and became lighter. Carbon Dioxide and water is given off in the smoke .

The chemical composition is changed

• Burning is a Chemical property which resulted in a Chemical change where the chemical makes up in the paper changed and it is irreversible

Ex. of Chemical Properties

• Flammability : Can be burned

• Rusting : Iron and Oxygen interacting

• Reactivity with Vinegar

• Toxicity : Poisoning of cells

• Acidity

​The ability to be burnt

​​Flamablity

​Metal reacting with oxygen and water

​​Rusting

Reactivity with Acid

​The ability to erode or eat away

​​Corrosivity

​The quality of being poisonous

​​Toxicity

Chemical Change

A chemical change occurs when a chemical reaction takes place where bonds are broken and new bonds are formed.

Chemical Reaction

- A CHEMICAL REACTION results in CHEMICAL CHANGE

- A chemical reaction is where one or more substance reacts forming a new substance

• The breaking and forming of new bonds results in the formation new substances

• The chemical makeup of the new substance is different from the original one

• What remains as ash may be calcium, magnesium, potassium, and phosphorus

• Burning of paper

• Rusting of Pennies

• Fried Egg

• Firework Exploding

• Digestion of food

• Reaction with Acids

• Respiration

Substance used is CHANGED. It is irreversible

​​Fireworks

The make up of the egg is CHANGED. The change is irrevesible

Frying Egg

​The banana's composition is CHANGED .

The change is irrevesible

​​Rotten Banana

​The food that we eat is CHANGED in our digestive system. The chamge is irreversible

Digestion

Fill in the Blank

A chemical change occurs when a ______________ takes place where bonds are broken and new bonds are formed.

Multiple Choice

When a new substance is formed with different properties than the original substance it is called a...

• Chemical change

• Physical change

• Change in State

• Change in appearance only.

Multiple Choice

Which type of change are irreversible?

• Chemical Changes

• Physical Changes

• Changes in State

• Changes in Temperature

Multiple Choice

If the chemical properties of a substance remain unchanged & the appearance or shape of an substance changes it is a...

• Chemical Change

• Physical Change

• Both a physical and chemical change.

• Neither a physical or chemical change.

Multiple Choice

Identify what type of change happening in the picture below...

• Chemical Change

• Physical Change

• Endothermic Reaction

• Exothermic Reaction

Multiple Choice

Identify what type of change happening in the picture below...

• Chemical Change

• Physical Change

• Endothermic Reaction

• Exothermic Reaction

Multiple Choice

What does a chemical change result in?

• A change in state of the substance (ex. liquid to solid)

• A change in texture of the substance.

• A change in the way atoms are bonded to each other.

• A change in the appearance of the substance.

Match

Match the following

• Change of State

• Acidity

• water evaporating

• Paper torn into small pieces

Physical

Chemical

Physical

Physical

• Physical

• Chemical

• Physical

• Physical

Drag and Drop

The breaking and forming of new ​

Placeholder

results in the formation ​

Placeholder

substances

The ​

Placeholder

makeup of the new substance is different from the ​

Placeholder

one

Drag these tiles and drop them in the correct blank above

bonds

new

chemical

original

physical

Chemical

Draw

Place checks beside the properties which are Chemical properties and X beside Physical properties

Open Ended

What are some signs that a chemical is taking place ?

Evidence of Chemical Change

• Color

• Formation of gases

• Precipitate

• Temperature Change

Color change in Chemical Reaction

Formation of gases

• Oxygen given off will relit a glowing flint

• Carbon Dioxide production will put out flame

• Hydrogen production will produce a popping sound with a glowing flint

Precipitation

A precipitate is an insoluble compound formed when two substances react

Temperature change

• When heat is given off it is called an Exothermic Reaction

• Reaction will feel warm to the touch

• When heat is absorbed it is called Endothermic Reaction

• Reaction will feel cold to the touch

Multiple Choice

If a chemical reaction is EXOTHERMIC, the temperature would....

• Stay the same

• Increase

• Decrease

Multiple Choice

Is photosynthesis an exothermic or endothermic reaction?

• Endothermic

• Exothermic

• Neither

Multiple Choice

Exothermic reactions...

• Absorb energy

• Release energy

• Release Color

• Absorb Color

Multiple Choice

What type of reaction occurs in a hand warmer

• exothermic

• endothermic

Multiple Choice

In an endothermic reaction, heat is ...

• taken in or absorbed

• given out or released

Multiple Choice

Which of the following is a chemical change?

• water freezes to form ice

• sugar dissolves in water

• wood burns in a campfire

• a piece of metal expands when heated

Multiple Choice

Which of the following describes a precipitate?

• a liquid forms when a block of metal is heated

• a solid forms when one liquid is poured into another

• a gas forms when a solid is placed in a liquid

• bubbles form when an acid is poured on a rock

Multiple Choice

One of the signs of a chemical reaction taking place is:

• Bubbles are produced

• Reactants are not combining

• Products are not forming

• Color is not changing

Multiple Choice

Evidence of a chemical reactions is anything that shows -

• a new substance has formed

• a solid dissolved in a liquid

• interaction between 2 gases

• a change in the state of matter

Multiple Choice

Digesting your food is an example of

• chemical change

• physical change

Multiple Choice

Which of the following is NOT evidence that that a chemical reaction has occurred?

• produces light/heat

• production of a gas

• formation of a precipitate

• melting

Multiple Choice

Which of the following is NOT evidence that that a chemical reaction has occurred?

• produces light/heat

• production of a gas

• formation of a precipitate

• melting