Unit 6 Review Flashcards
How many other words can you think of that describe physical changes?
Crush Mash Split Crack Break Spray
What happens to water if you lower the temperature below zero degrees Celcius?
It freezes into solid ice.
What happens to water when you boil it?
It evaporates into water vapor (gas)
What are some other ways matter can change states?
Cooling gases often causes them to condense into liquids. Heating solids often causes them to melt into liquids
True of False
A physical change does not change the type of molecules that make up the substance.
True
You cut a piece of wood and sand it to make a model. What kind of change occurred?
Physical change
Which choice describes a physical change?
Cutting down a tree
Melting ice cream
Making lemonade from crystals
Which change is likely to be a physical to an object?
The shape of the object changed
What type of change will occur when the warm sun reaches icicles hanging from a rooftop?
Physical change
The shoelaces on Jen’s shoes were too long, so she decided to cut them. What type of change happened to her shoelaces?
Physical change
If you mix together flour, butter, chocolate chips, and a little baking soda, and shape it into flat circles, what kind of change have you made?
Physical change
If you mix together flour, butter, chocolate chips, and a little baking soda, shape it into flat circles, and put it in an oven for about 20 minutes, it turns into something very tasty. What kind of change has happened?
Chemical change
If you combine two types of matter and evergy is given off, what type of change is likely to have occured?
Chemical change
When you mix vinegar and baking soda, they experience a chemical change. What evidence below would lead you to think that the change is a chemical change?
The solution heats up or cools off
True or False
If one or more substances change into new substances, a chemical change occured
True
What are called the building blocks of molecules?
Atoms
What are called gas, gold, oxygen, and hydrogen?
elements
What is called something made up of more than one type of atom?
compound
How big is a atom?
10,000 times smaller than the width of a human hair
What composes an atom?
Nucleus (center) is made out of neutrons and protons(+), with electrons(-) circling it
Which do you think has greater mass, a hydrogen atom or an oxygen atom?
an atom of oxygen
What are the three parts of the atoms?
Protons
Neutrons
Electrons
True of False
The atoms that make up the element oxygen are exactly the same as the atoms that make up the element hydrogen.
False
True of False
Atoms of different elements can combine to form compounds
False
When two hydrogen atoms and one oxygen atom join together they form what compound?
Water
True of false
The element sodium is made of two kinds of atoms with differnt numbers of protons
false
On the periodic table, elements are represented by:
chemical symbols
Scientists organize all the known elements into a chart called the :
Periodic table
