1. Sections 1.3 and 1.4 Science 7 Mr. Nigh
Matter and Energy
Sections 1.3 and 1.4 Science 7
Mr. Nigh

2. Matter Combines to form different substances
Most of the substances in the world are mixed
Matter can be pure or it can be two or more substances mixed together
Drinking water may appear to be pure, but may have many minerals dissolved in it.
Often the difference between pure and mixed may only be visible on the atomic or molecular level

4. Elements
An element is a substance that contains only a single type of atom
The number of atoms is not important
An element cannot be separated into other substances

5. Gold
Silver

6. Compounds
Compounds are substances that consist of two or more different types of atoms bonded together
Some types are made of molecules such as water and carbon dioxide
Others are made of elements bonded together like salt

7. Salt

8. Salt is a compound that has very different properties then the elements that make it up
Sodium and Chlorine are poisonous by themselves
But when combined, they create a compound (table salt) that is safe to eat

9. Mixtures
A mixture is a combination of different substances that remain the same individual substances and can be separated by physical means
For example: a fruit salad is not a different kind of fruit, the parts can be separated by physical means

10. Fresh Fruit Salad

11. Parts of mixtures can be the same or different throughout
Soil
Several handfuls of soil may have different properties in different parts of your backyard
The soil in the yard is thus an example of a heterogeneous mixture, different properties in different parts of the mixture

12. Soil Layers

14. Kool-aid
You know the color and flavoring in Kool-aid are there because you can see and taste them
One drop of the liquid is essentially the same as another drop
Thus this is an example of a homogeneous mixture

15. Comparing mixtures and compounds
Substances in mixtures remain the same, in compounds new substances are formed by atoms that bond together
Mixtures can be separated by physical means, compounds only by breaking bonds
Proportions in mixtures vary, compounds are fixed because the type and number of atoms are always the same

16. States of Matter
The four familiar states of matter are solid, liquid, gas and plasma
When a substance changes from one state to another, the molecules in the substance do not change
However the arrangement of molecules does change giving each state of matter its own characteristics

17. Solid It has a fixed volume and a fixed shape
Particles are close together and form a regular pattern
Particles cannot move from one location to another, fixed

19. Liquid Liquid has a fixed volume, but no fixed shape
Usually the shape of the container it is in
Particles are attracted and close, but are not fixed and may move from one place to another

21. Gas A gas has no fixed volume or shape
Particles are not close together and may move from one place to another
Space between particles can increase or decrease with pressure

23. Gas Behavior
Gas molecules are always in motion, continually hitting each other and applying pressure to the sides of any container they are in
As in a bicycle tire, the more molecules are put in, the harder the outside of the tire becomes
The speed at which gas molecules move depends on the temperature, higher temperature molecules move faster

24. Plasma
Although it is the least familiar state of matter to us here on Earth, plasma is actually the most common form of matter – 99% of all visible matter in the Universe.
In a plasma, a significant number of electrons have such high energy levels that no nucleus can hold them.

25. Earth Plasma examples

26. Plasma in the universe
Horsehead nebula
Orion Nebula

27. Egg Nebula

28. Plasma on the Sun

30. --Difficult Concept-- Listen
Volume, temperature, and the pressure of gasses have a unique relationship
--Difficult Concept-- Listen
Increase
Decrease
Stay the same

31. If the temperature of the gas stays the same, increasing the pressure of the gas decreases its volume
If the volume stays the same, increasing the temperature increases the pressure
If the pressure of the gas stays the same, increasing the temperature of the gas also increases the volume

32. Which two characteristics determine the state of matter?
The arrangement and the motion of particles

33. Which state of matter has particles that are farthest apart?
Gas

34. Which state of matter has particles that are generally close together?
Solid

35. Which state of matter has particles that can slide past each other but cannot move freely in any direction
liquid

36. What happens to the volume of a gas if the temperature stays the same and the pressure on the gas increases? It
decreases

37. What happens to the pressure of a gas if the volume stays the same and the temperature increases?It
increases

38. What happens to the volume of a gas if the pressure stays the same and the temperature increases?It
increases

39. The
End