2.2 - Matter & Its Changes

Signs of a Chemical changes

Physical Properties

A characteristic that can be observed or measured without changing the identity of the substance is called a physical property. Your senses can be used to detect properties like color, shape, size, texture, taste and odor among others. The way you described your favorite fruit was a list of it's physical properties.

Multiple Choice

A physical change...

• changes the physical properties of an object, but does not create a new substance.

• creates a new substance and cannot be undone.

Multiple Choice

What kind of change occurs if matter changes in amount, size, or shape?

• substance change

• chemical change

• physical change

• elemental change

Multiple Choice

Which of the following is NOT an example of chemical change?

• sour milk
• burning wood
• breaking a pencil
• rust

Multiple Choice

Review the information in the graph. Which of these statements is true?

• The change from ice of liquid water is a chemical change.

• The change from liquid water to water vapor is a physical change.

• It takes the same amount of time for ice to melt as it does for liquid water to become water vapor.

• The change from ice to liquid water to water vapor shows a decrease in mass due to the changes in states of matter.

Physical Properties

A characteristic that can be observed or measured without changing the identity of the substance is called a physical property. Your senses can be used to detect properties like color, shape, size, texture, taste and odor among others. The way you described your favorite fruit was a list of it's physical properties.

Multiple Choice

Which of the following are considered physical properties?

• Length

• Temperature

• Mass

• All of the options are correct.

Multiple Choice

Benny decides to bend a copper wire so that it fits into his computer better. Is this an example of a physical change?

• Yes because the chemical composition of the wire does not change.

• No because the chemical composition of the wire changes.

• Yes because the chemical composition of the wire changes.

• No because the chemical composition of the wire does not change.

Multiple Choice

Carson decides to cut his hair. Is this an example of a physical change?

• Yes because the chemical composition of his hair does not change.

• No because the chemical composition of his hair changes.

• Yes because the chemical composition of his hair changes.

• No because the chemical composition of the wire does not change.

Multiple Choice

What is one thing that ice, liquid drinking water, and water vapor have in common?

• They all have equal amounts of kinetic energy.

• They all have equal amounts of thermal energy.

• All three are made of the same particles - H2O.

• All three are the same state of matter.

Multiple Choice

Is this image of a physical or a chemical change?

• Physical

• Chemical

• Both

Multiple Choice

Is this image of a physical or a chemical change?

• Physical

• Chemical

• Both

Multiple Choice

Is this image of a physical or a chemical change?

• Physical

• Chemical

• Both

Multiple Choice

Is this image of a physical or a chemical change?

• Physical

• Chemical

• Both

Multiple Choice

Is this image of a physical or a chemical change?

• Physical

• Chemical

• Both

Multiple Choice

Is this image of a physical or a chemical change?

• Physical

• Chemical

• Both

Multiple Choice

Is this image of a physical or a chemical change?

• Physical

• Chemical

• Both

Multiple Choice

Is this image of a physical or a chemical change?

• Physical

• Chemical

• Both

Multiple Choice

Is this image of a physical or a chemical change?

• Physical

• Chemical

• Both

Multiple Choice

Is this image of a physical or a chemical change?

• Physical

• Chemical

• Both

• occur when one substance changes into another​ after a chemical reaction

• ​"ingredients" are called reactants and end results are called products

• irreversible​

Chemical Changes

Multiple Choice

A chemical change

• changes the physical properties of an object, but does not create a new substance.

• creates a new substance and cannot be undone.

• Production of gas/bubbles​

• Production of odor

• Change in color

• Formation of precipitate

• Exothermic/Endothermic reaction

• ​Release of light

​

Identifying chemical changes

​Signs of a chemical change

​

Chemical reactions tend to happen more quickly at higher temperatures. When temperatures are higher, atoms and molecules have more kinetic energy which enable them to move around and rearrange more quickly and easily.

Multiple Choice

Which of the following is NOT an example of a physical change?

• Smashing a soda can

• Wood breaking apart

• Salt dissolving in water

• Iron rusting

Multiple Choice

A change where one or more new substances are created.

• Physical Change 
• Chemical Change 

Multiple Choice

Which of these is a result of a chemical change?

• A mixture
• A solution
• A new substance
• Melting or freezing

Multiple Choice

Which of the following is a sign that a chemical reaction has occurred?

• change in shape
• melting
• formation of a gas
• dissolving

Multiple Choice

Physical or Chemical Change?  Baking a cake.

• Chemical Change
• Physical Change

Multiple Choice

Matter can not be created nor destroyed: it can only be

• Destroyed a little bit
• Invisible
• Transformed, changed
• None of the above

Chemical Properties

A chemical property describes a property that is only observed when a substance changes into a new substance with different properties. Like when iron rusts and turns into a new substance called iron oxide.

Chemical changes

A chemical change occurs when one or more substances change into entirely new substances. In a chemical change, the chemical identity of a substance changes and a new substance is formed that has different properties.

Signs of a Chemical changes

Multiple Choice

Which phrase most accurately describes a chemical change?

• A change on the molecular level

• A change in appearance

• A change in taste

• A change in form

Multiple Choice

How are physical and chemical properties different?

• Chemical properties only apply to chemicals. Physical properties apply to everything.
• Chemical properties are only observable as the substance is changing. Physical properties are easily observed or measured.
• Chemical properties are easy to reverse, and physical properties cannot be reversed. 

Multiple Choice

Which answer makes the sentence true. 
Matter is anything that _______________________________. 

• is burned to make heat
• takes up space and has mass
• lets electricity move through it

Multiple Choice

Which is NOT a physical property?

• odor
• reacts with acid
• ability to conduct electric current
• hardness

Multiple Choice

Which one of these is a chemical property?

• melting point
• boiling point
• color
• flammability

Multiple Choice

Photosynthesis is an example of a

• physical change
• chemical change

Multiple Choice

Which of the following IS a clue that a chemical change has occurred? 

• State of matter change
• Size Change
• Change in temperature
• Shape change

Multiple Choice

Is mold growing on cheese a physical or chemical change?

• Physical 
• Chemical

Multiple Choice

Is milk going sour a physical or chemical change?

• Physical 
• Chemical

Multiple Choice

How does rust form?

• Through paint flaking off of a metal surface

• Through a chemical reaction between iron and oxygen

• Through weathering

• Through the physical mixing of iron and water

Multiple Choice

What is an example of a chemical change that happens inside your body?

• Food being broken down by enzymes in your stomach

• Food being broken into small pieces by your teeth

• Food being moved from your esophagus into your stomach

• Water being absorbed inside your large intestine

Multiple Choice

What is happening when your body changes the food you eat into energy you need to grow?

• a chemical change

• a physical change

• a chemical property

• a physical property

Physical vs Chemical Changes

How do you know which type of change has occurred?

Multiple Choice

If two substances are mixed and a new substance is formed, what type of change is it?

• Physical

• Chemical

Multiple Choice

When a substance changes states (melts, evaporates, etc.) it is often what type of change?

• Physical

• Chemical

Multiple Choice

When something burns, it is a __________.

• Physical Change

• Chemical Change

Multiple Choice

True or false: since gas is detected during the candy + soda demo, it is an example of a chemical change.

• True, anytime a gas is formed during a reaction it is always a new type of gas.

• False, the gas that is detected during the reaction may be a gas the same gas that was present before the reaction took place.

Law of Conservation of Mass

Balanced or Unbalanced Equations

Multiple Choice

The Law of Conservation of Mass states Matter is NEITHER created nor destroyed.

• True

• False

TRUE!

The Law states matter is neither created nor destroyed as seen in this image. We started with 100g and when we broke apart the elements they STILL equal 100g of mass.

Multiple Choice

The number in front of a compound or element is a 

• Subscript
• Coefficient
• Superscript
• Charge

Multiple Choice

The Coefficient (3) in the Chemical Formula, 3H₂O, tells you how many _____________ there are.

• Atoms of Hydrogen

• Atoms of Oxygen

• Atoms of Water

• Molecules of Water

Multiple Choice

The number to the lower side of an element is a 

• Subscript
• Superscript
• Coefficient
• Charge

Multiple Choice

How many oxygen atoms are in this chemical formula?

• 6 oxygen atoms

• 2 oxygen atoms

• 3 oxygen atoms

• 4 oxygen atoms

Reactants (Term)

• The substances in a chemical reaction that chemically combine

• Examples would be the combination of sodium and chlorine

Products (Term)

• The new substance made after a chemical reaction

• Examples include Salt (NaCl) after sodium and chlorine combine

Precipitates (Term)

• A solid that forms after two liquids chemically react (definition)

• Examples would include the combination of milk and vinegar

Multiple Choice

When two hydrogens chemically combine with one oxygen would what would water be?

• Reactant

• Product

• Precipitate

Evidence of a chemical change

• Abbreviation to remember = City, Girls, Like, To, Order, Pizza

• C: color change

• G: Gas

• L: Light is produced

• T: Temperature change

• O: odor is produced

• P: Precipitate is formed

Multiple Choice

What does the o stand for in the acronym that we learned?

• Gas

• Light

• Odor

• Osmosis

Multiple Choice

A chemical reaction is balanced when

• both sides have the same elements
• Both sides have the same  number of atoms
• Same subscripts
• Same coefficients

Multiple Choice

If a reaction starts with a total 75g of reactants it should produce 

• a total of 40g of products
• a total of 75g of products
• a total of 180 g of products
• None of the above

Multiple Choice

24 g of magnesium reacts with 38 g of fluorine to produce _____ g magnesium fluoride

• 62 
• 38
• 24
• 14

Multiple Choice

32 g of Oxygen completely reacts with 8 g of Hydrogen to produce _____ g Water

• 8

• 12

• 24

• 40

Multiple Choice

What is the arrow in a chemical equation...
H_{2 +} O --> H₂O

• Reactants
• Products 
• Yields 
• Chemical Equation 

Multiple Choice

How many elements does PbNO₃ have?

• 2
• 3
• 4
• 5

Multiple Choice

How many nitrogen atoms does NH₃ have?

• 1
• 2
• 3
• 4

Multiple Choice

Which equation best represents the law of conservation of mass? 

• A
• B
• C
• D

Multiple Choice

Is this balanced?
2HgO → 2Hg + O₂

• Yes
• No

Multiple Choice

Is this equation balanced or unbalanced?

CH₄ + 2O₂--> CO₂+ 2H₂O

• balanced

• unbalanced

Multiple Choice

12g of Carbon react with 16g of Oxygen, how much carbon monoxide (CO) is formed? 

• 28 g
• 4g
• 30g
• 12g

Multiple Choice

Is this equation balanced or unbalanced? 
H₂ + O₂ --> H₂O

• balanced
• unbalanced

Multiple Choice

A ___ change causes the substance to change to a new substance with different properties.

• Physical

• Chemical

Multiple Choice

A ____ change only changes the look of the substance but NOT the chemical make-up.

• Physical

• Chemical

Multiple Choice

Is it a physical or chemical change?

• physical

• chemical

Multiple Choice

Is it a physical or chemical change?

• Physical

• Chemical

Multiple Choice

Vinegar + baking soda reaction.

Is it a physical or chemical change?

• Physical

• Chemical

Multiple Choice

Is it a physical or chemical change?

• Physical

• Chemical

Multiple Choice

Rotting banana

Is it a physical or chemical change?

• Physical

• Chemical

Multiple Choice

Is it a physical or chemical change?

• Physical

• Chemical

Multiple Choice

Water + Kool-aid Powder.

Is it a physical or chemical change?

• Physical

• Chemical

Multiple Choice

The metal is rusting.

Is it a physical or chemical change?

• Physical

• Chemical

Multiple Choice

Leaves changing colors in the fall.

Is it a physical or chemical change?

• Physical

• Chemical

Multiple Choice

Mixing sugar and water.

Is it a physical or chemical change?

• Physical

• Chemical

Multiple Select

Choose all of the following that are PHYSICAL changes.

Multiple Select

Choose all of the following that are CHEMICAL changes.

Poll

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