Properties of Matter and Substances Flashcards
Pure substance
matter that always has the same composition - sugar, salt
element
matter that can’t be broken down into simpler substances – copper, gold, carbon ONLY 1 TYPE OF ATOM
atom
smallest particle of an element
Jons Berzelius
Swedish man who came up with symbols for elements
molecule
group of atoms joined together by covalent bonds
compound
matter that is made up of two or more simple substances - they can be broken down - WATER IS A COMPOUND - oxygen and hydrogen
Mixtures
they keep some of properties of their ingredients - salsa
heterogeneous mixtures
parts of a mixture are different from one another - SAND IS AN EXAMPLE
homogeneous mixture
can’t see the different substances in the mixture - WATER IN SWIMMING POOL
colloid
milk is a colloid - can’t separate with filter fog is a colloid
solution - homogeneous
when substances dissolve - THEY DO NOT SEPARATE INTO LAYERS - windshiel wiper fluid
suspensions - heterogenous
mixture that separates into layers over time - YOU CAN USE A FILTER - WATER AND SAND
physical property
characteristic of a material that can be measured without changing the substances in the material
Examples of physical properties
viscosity, melting point, density, malleability, conductivity, hardness
Why study physical properties
They help people identify material, pick which material to use for a job, or to help separate mixture for a purpose
Filtration and distillation
Two ways to separate mixtures!!!!
Physical change
properties of a material change but substances in material are the same SUBSTANCE IS THE SAME
Examples of physical change
freeze water, melt ice, freeze water again
melt butter in pan but still butter
cut hair
slice tomatoes
Chemical property
ability to produce a change in the composition of matter
Two chemical properties
flammability, reactivity
Chemical change
this happens when a substance reacts or forms into one or more substances - THERE IS A CHANGE
evidence of chemical change
color change - banana, copper roof
produce gas- vinegar and baking soda
precipitate - curdling milk
