Physical Vs. Chemical Changes - Explained
Summary
TLDRIn this educational video, Mr. Millings explores the distinction between physical and chemical changes. He illustrates physical changes as alterations in form without altering the substance's chemical identity, using examples like grinding peanuts into butter, folding paper into an airplane, and melting ice. Chemical changes, in contrast, involve a transformation in the substance's identity, such as fermentation of sugar to alcohol, oxidation of iron to rust, and electrolysis of water into hydrogen and oxygen. The video clarifies that all chemical changes include physical changes, but not all physical changes involve chemical alterations.
Takeaways
- đ Physical changes involve alterations in a substance's physical form without changing its chemical identity, such as grinding peanuts into peanut butter.
- đ All changes in the state of matter, like melting ice into water, are considered physical changes.
- đ Physical changes are not necessarily accompanied by chemical changes, as seen when copper is turned into wire, maintaining its chemical composition.
- đŹ Chemical changes result in a new substance with a different chemical makeup, like fermentation turning sugar into alcohol.
- đż Oxidation, such as an iron nail rusting, is an example of a chemical change where the iron combines with oxygen to form a new substance.
- đ„ Combustion, like burning logs, is a chemical change that alters the chemical composition of the material.
- đ§ Electrolysis of water, which splits it into hydrogen and oxygen gas, is a chemical change creating new substances.
- đ§ Souring of milk is a chemical change as it breaks down into different substances over time.
- đĄïž Sublimation of dry ice, turning it from a solid to a gas without becoming a liquid, is a physical change in state.
- đș Fermentation of sugar into alcohol is a chemical change, transforming one chemical substance into another.
- đ«ïž Evaporating water, turning it into water vapor, is a physical change in state of matter.
Q & A
What is the main difference between physical and chemical changes?
-Physical changes involve alterations in the physical form or state of a substance without changing its chemical identity, while chemical changes involve a transformation that results in a new substance with a different chemical makeup.
Can you give an example of a physical change from the script?
-Grinding peanuts into peanut butter is an example of a physical change because the peanuts are simply changed in form, not in chemical composition.
What is the significance of the term 'ductility' mentioned in the script?
-Ductility refers to the property of a metal that allows it to be stretched into a wire. In the script, turning a copper bar into copper wire demonstrates the ductility of copper.
How does the script explain the melting of ice as a type of change?
-The melting of ice into liquid water is described as a physical change because it's a change in state from solid to liquid, but the chemical composition (H2O) remains the same.
What is the key takeaway from the script about changes in the state of matter?
-All changes in the state of matter, such as from solid to liquid or liquid to gas, are considered physical changes because they do not involve a change in the chemical identity of the substance.
According to the script, are all physical changes accompanied by chemical changes?
-No, the script clarifies that not all physical changes are accompanied by chemical changes. Physical changes can occur without altering the chemical composition of a substance.
What is an example of a chemical change given in the script?
-The fermentation of sugar into alcohol is an example of a chemical change because it results in a new substance with a different chemical composition.
What process is described in the script when an iron nail turns into a 'Rusty Nail'?
-The process described is oxidation, where the iron nail reacts with oxygen to form iron oxide, commonly known as rust, indicating a chemical change.
How does the script illustrate the concept of combustion as a chemical change?
-The script uses the example of burning logs, where the chemical composition of the logs changes due to the combustion process, resulting in new substances.
What is electrolysis, and how does it relate to chemical changes according to the script?
-Electrolysis is the process of passing an electric current through water to separate hydrogen from oxygen, creating hydrogen gas and oxygen gas. The script states that this is a chemical change because it transforms one substance into two different substances.
What is the script's final point about the relationship between physical and chemical changes?
-The script concludes that while all chemical changes are accompanied by physical changes, the reverse is not true; not all physical changes involve chemical changes.
Outlines
đ Physical vs. Chemical Changes
This paragraph introduces the concepts of physical and chemical changes. Mr. Millings explains that physical changes involve alterations in the physical form of a substance without changing its chemical identity, using examples such as grinding peanuts into peanut butter, folding paper into an airplane, shaping copper into wire, and melting ice. He emphasizes that all changes in the state of matter, like ice melting, are physical changes and that physical changes do not involve a change in chemical composition. The paragraph concludes by noting that physical changes are not always accompanied by chemical changes.
đŹ Examples of Physical and Chemical Changes
The second paragraph delves into more examples to distinguish between physical and chemical changes. It starts by confirming that condensing water vapor is a physical change due to a change in state. Then, it discusses the combustion of gasoline as a chemical change, where gasoline is converted into different substances. The paragraph also covers the electrolysis of water into hydrogen and oxygen gases as a chemical change, the souring of milk due to the breakdown into different substances, and the sublimation of dry ice as a physical change. Additionally, it mentions turning copper into wire as a physical change due to a change in form but not in chemical composition, the fermentation of sugar into alcohol as a chemical change, and evaporating water as a physical change involving a state change from liquid to gas. The summary ends by reinforcing that all chemical changes involve physical changes, but not all physical changes involve chemical changes.
Mindmap
Keywords
đĄPhysical Change
đĄChemical Change
đĄIdentity
đĄChemical Makeup
đĄDuctility
đĄState of Matter
đĄFermentation
đĄOxidation
đĄCombustion
đĄElectrolysis
đĄSublimation
Highlights
Introduction to the concept of physical versus chemical changes.
Definition of physical changes as alterations that do not affect the substance's chemical identity.
Example of grinding peanuts into peanut butter as a physical change.
Folding paper into an airplane illustrates a physical change without altering chemical makeup.
Explanation of ductility as the ability to turn metals like copper into wire, a physical change.
Melting ice to water as an example of a physical change, maintaining the chemical composition of H2O.
All changes in state of matter are identified as physical changes.
Clarification that physical changes do not necessarily involve chemical changes.
Introduction to the concept of chemical changes involving a change in the substance's identity or chemical makeup.
Fermentation as a chemical change turning sugar into alcohol, a different substance.
Oxidation of an iron nail turning it into rust, a chemical change.
Combustion or burning as a process that results in a chemical change.
Electrolysis of water into hydrogen and oxygen gas as a chemical change.
All chemical changes are accompanied by physical changes, but not vice versa.
Examples provided to distinguish between physical and chemical changes.
Condensation of water vapor as a physical change due to a change in state of matter.
Combustion of gasoline as a chemical change involving the conversion of gasoline into different substances.
Electrolysis of water as a chemical change resulting in two different substances.
Souring of milk as a chemical change due to the breakdown into different substances.
Sublimation of dry ice as a physical change, transitioning from solid to gas without becoming a liquid.
Turning copper into wire as a physical change with no change in chemical composition.
Fermentation of sugar into alcohol as a chemical change, transforming one chemical substance into another.
Evaporation of water as a physical change, changing from liquid to gas.
Conclusion summarizing the differences between physical and chemical changes.
Transcripts
[Music]
hey you guys this is Mr millings and
today we're going to talk about physical
versus chemical changes so what are
physical changes well it says right here
that physical changes are changes in a
substance that do not involve a change
in the Identity or chemical makeup of
that substance so let's take a look at a
few examples here down below let's
suppose we have some peanuts and what
we're going to do is we're going to
grind these peanuts down to make peanut
but
we still have peanuts here and we still
have peanuts here it's just taken on a
different physical form so this is going
to be a physical change this would be
example of a physical change right here
grinding peanuts into peanut butter
let's take a look at this piece of paper
right here if we fold this piece of
paper up to make a paper airplane this
would be an example of a a physical
change we're not changing the chemical
makeup of the paper we're simply
changing its physical appearance over
here if we take a look at this copper
bar right here what we're going to end
up doing is we're going to end up
turning this into copper wire and
anytime you can take a metal and turn it
into wire that uh that that shows that
that that metal is
ducal okay ducal is the process or
ductility is the process of turning uh
metal into wire so we still have copper
here and it's still copper here it's
just taking on a different physical form
let's take a look right here we have ice
which we know is
H2O that's water in the solid stage or
state and what we're going to do with
this ice is we're going to melt it down
into liquid water so it's still H2O here
we did not change the chemical makeup of
this uh we just changed the physical
appearance so this too would be a
physical change all right so once again
changes in a substance that do not
involve a change in the Identity or
chemical makeup of that substance are
physical changes and it's important to
keep in mind and this is very important
that all changes in state of matter are
going to be physical changes so anytime
you go from solid to liquid or liquid to
gas or gas to liquid and liquid back to
solid it's going to be a physical change
just like the ice melting over here that
is going to be a physical change all
right lastly it says all physical
changes are not necessarily accompanied
by a chemical change and we'll talk
about chemical changes in a second but
understand that when we when we take
these peanuts and make peanut butter out
of it we're not changing the chemical
composition okay this is only going to
be a physical change same right here
same thing right here and same thing
right here okay okay so now let's take a
look at chemical
changes okay it says right
here that chemical
changes are changes in a substance that
do involve a change in the Identity or
chemical makeup of that substance so if
we take a look here if we have some
sugar here and we end up making some
type of alcohol over here that process
is called fermentation fermentation is
the process of turning sugar into
alcohol so we have sugar over here which
is one type of compound and we have
alcohol over here which is a totally
different substance and so that is going
to be a chemical change another example
right here if we have an iron nail and
we leave it out uh on the grass
overnight uh it might turn into this
Rusty Nail over time right that process
is called oxidation right uh the iron
nail here the iron is combining with
oxygen to produce uh some iron oxide or
rust over here that is going to be a
chemical change the chemical composition
position of this nail now is different
than when than what we started with if
we take a look right here we have some
logs here and if we light these logs on
fire like we see right here this will be
an example of a chemical change right
this is going to be a chemical change
anytime we burn something or anytime
there's some sort of combustion going on
that's going to be a chemical change
we're changing the chemical composition
of these of these logs if we take a look
right here if we take some water which
is uh made of of two hydrogen's bonded
to one oxygen and we pass an electric
current through it what ends up
happening is the
hydrogen the hydrogens break free from
the oxygen and end up producing hydrogen
gas and oxygen gas okay so we have one
substance over here which is water and
we have two brand new substances over
here which is hydrogen gas and oxygen
gas and this too would be an example of
a chemical change okay so one last thing
that you need to keep in mind and this
is very important as well it says right
here that all chemical changes are
accompanied by physical changes so
primarily all of these are going to be
examples of chemical changes but there's
a physical change also if you take a
look there's a physical change in the
appearance here there's a physical
change in the appearance of these logs
there's a physical uh change in the
appearance of the iron nail there's a
physical change in the appearance of
this water so all chemical changes are
accompanied by a uh physical change but
the opposite is not true not all
physical changes are accompanied by
chemical changes okay so here are some
examples of physical and chemical
changes let's now take a look at a few
more and see if you can determine which
is
which okay so let's just quickly go
through each one of these examples here
and what we need to do is determine if
it is a physical or chemical change and
once again we will assume that all
chemical changes are also physical
changes so right here if we have
condensing water vapor so that's water
vapor that is turning back to a liquid
that is a change in state of matter that
will always be a physical
change let's look at this next one the
combustion of gasoline okay so when gas
gasoline catches on fire what's
happening is that there's a chemical
change going on that gasoline is being
converted into something else or
something totally different so this will
be an example of a chemical change let's
look at this next one turning water into
hydrogen and oxygen gas we just talked
about electrolysis and anytime you're
turning one thing
or one chemical into two different
chemicals or one substance into two
different substances that's going to be
a chemical change as
well let's look at this one milk souring
so over time what happens is that milk
is breaking down and it's being
converted into different substances so
that's going to be a chemical
change let's look at this one the
sublimation of dry ice so sublimation
that's the process of going from a solid
directly to a gas without passing the
liquid stage first and in a different
video we talked about that so that's
going to be a change in state of matter
and that's going to be a physical change
remember all changes in states of matter
are always physical changes what about
turning copper into wire turning copper
into wire it's still going to be copper
it just has a different physical form so
that is a physical change as well let's
look at this one the fermentation of
sugar into alcohol we talked about this
uh few moments ago we are turning sugar
into something totally different we're
turning one chemical substance into a
different chemical substance so that
will be a chemical
change and last but not least we have
evaporating water evaporating tells you
that that liquid is turning into a gas
in this case water vapor so that is
going to be a change in state of matter
and all changes in state of matter are
physical
changes okay so that's physical and
chemical changes in a nutshell if you
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and I hope this was
helpful
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