today we will be talking about a new concept but I'm not going to tell you
exactly what that concept is yet I wanted to hit on the fact that we
already know that any kind of object or item or any kind of matter can be
classified or categorized and we know this because we have groups in our
classroom we have different desks we have the red group in the blue group and
the yellow group and the green group and we always lineup in different types of
categories. I'll say anybody that's wearing tennis shoes lineup, anybody
that's wearing a jacket or anyone that's wearing shorts or pants. There's a
bunch of different kinds of ways that I can classify and categorize our class
and that goes for any object or any type of matter in the world we can classify
and organize all sorts of things so that's what we're going to be talking
about today something along those lines of
classifying and how we organize different matter so if you know a way or
a characteristic of something that you would classify and observe about an
object raise your hand and share that with me and the rest of your class... so
our observable property for example was the word soft. we can describe
something as being soft this is an observable property of matter we know
this because it is a property that can be observed with our five senses we use
our five senses to observe different types of matter and that's how we learn
their properties so for example we have this ball here I'm going to use my five
senses that I have to observe the ball and find
its observable properties a property is a characteristic so let's just remember
that when we're observing so I'm observing this ball by using my five
senses so first I'm gonna use my eyes when I use my eyes I can see that this
ball is pink the ball is around the ball is if I just look at it and don't feel
it it's spiky it looks like it has little spikes on it now when I use my
hands to feel it I'm gonna squish it and I can see that it's it is squishy it is
stretchy I can stretch these little guys here I can feel that it's kind of bumpy
when I rub my hand along it I can smell this I can smell that it smells like
rubber which that explains why it's stretchy rubber is usually stretchy I'm
not gonna taste it because I'm just... don't think it's anything that's edible
but I can hear it if I rub my hand along it I can hear the way that the little
bristles that it has when they pop I can hear that so I know that it's definitely
making noises from being able to be moved it's definitely not hard I can
move these so these are all observable properties of this ball so let's look at
something else I have this little box here with Mickey and Minnie on it I'm gonna
see if this box has observable properties like the ball does which it
will have observable properties but they don't have to be the same as the ball
and in fact they could all be different so I'm gonna use my eyes first to
observe this box I can see that it's definitely not round and we know
that it's not round because it doesn't have curved surfaces like the ball does
but it has flat smooth surfaces I can feel that with my hand and I can see it
with my eyes I don't think I'm gonna I don't think smelling it would really
help me so we'll skip that one and I don't think tasting the box is going to
help me in any way either so I can hear it if I tap my finger on it which tells
me that it sounds like it's hard because I hear like a little echo it's like
because it's tin so it's a very hard and strong as I use my hands to squish it,
try to squish it like with the ball it's not very squishy it's very hard so those
are our observable properties of this box that I have here now a common
misconception is that if you were to have something that is squishy or
stretchy that once you stretch it or once you break it that that changes its
identity completely so let me tell you what I mean here so I have this rubber
band here I'm going to stretch it as far as I can and let's say I even I don't
know if I'm strong enough but if I break this rubber band because it's very
stretchy its breakable that's an observable property of this rubber band
now if I break it does that change the identity of the rubber band no it
doesn't it's still a rubber band I can put it in water I can stretch it and
break it I can do almost anything that I want to it and it doesn't change the
identity of the rubber band so it being stretchy and breakable is an observable
property but an observable property is only one that does not change the
identity of the matter so if it's something if you have if you have matter
and whatever happens to if it changes to something else
afterwards completely something else it's not the same anymore
chemically then that isn't it's no longer the same identity it is something
different so there we go so also another misconception that's along those lines
is water and freezing and boiling points so if you have water in liquid form it's
going to take the shape of whatever container that it's in so that would be
an observable property the shape that is if it's in a a spherical bowl then it's
going to be circular because it's water it's gonna take whatever kind of shape
that you give it whatever kind of container that it's in so if you freeze
it it now becomes ice now it chemically is still the same it's still h2o it's
still water it's just water in a different form it's frozen that freezing
point is an observable property because we can see and we can observe that it is
now frozen the same thing goes for water when it turns into water vapour when it
hits its boiling point once it starts boiling it starts to evaporate and turn
into water vapour so these freezing and boiling points are misconceptions
because a lot of students think that once it is once water goes to ice that
ice is not water anymore but it is still the same thing chemically it has not
changed its identity just it's observable property it is now hard and
frozen whereas the water was liquid and it can take any kind of shape depending
on what you put it in so those are some common misconceptions about observable
properties with matter
For more infomation >> Erosion Video project - Duration: 4:50. 
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