Unit 3 Study Guide

Bozenmayer, Alexander, Albano

2014 – 2015

Anything with mass AND volume.

X

X

EMade of only 1 type of atom

C M

C

Two elements in fixed amounts

Two elements in fixed amounts

Different compounds physically combined

Mixture that does not appear to be the same throughout

Mixture that appears to be the same throughout

Sand, trail mix

Salt water, syrup

Anything with mass AND volume.

2 or more elements that are chemically combined in fixed amounts

X

X

Mixture that does not appear to be the same throughoutSand, trail mix

Mixture that appears to be the same throughout

Salt water, syrup

A

C

B

D

C

P

C

C

P

P

Just changing shape/size.

Color change due to reaction.

Yeast rises due to reaction.

Just changing shape.

Phase changes are physical changes.

D

C

D

D

D

P

C

C

P

P

Just changing shape/size.

Just changing shape/size.

Color change due to reaction.

Yeast rises due to reaction.

Phase changes are physical changes.

Part 1. Elements, Compounds, Mixtures (Study your “Graphic Organizer” notes, and “Stations Activity”, “Elements, Compounds, Mixtures” graded assignment, “Elements, Compounds, Mixtures” quiz and think back on the sludge lab)

21. What is the definition and an example of a heterogeneous

mixture?• Heterogenous mixtures are made of 2 or

more elements, but keep their properties. They are unevenly mixed and do not appear the same throughout. Sand and trail mix are two examples.

22. What is the definition and an example of a homogeneous

mixture?• Homogeneous mixtures are made of 2 or

more elements, but keep their properties. They are evenly mixed and appear the same throughout. Sugar water and syrup are two examples.

23. What was the big idea for elements, compounds, and mixtures?

Part 2. Physical/Chemical Changes (Study your

“Physical/Chemical Change” demo sheet, think back on your “Physical/Chemical

Changes” graded assignment, and “Chemistry

in a Bag” lab)

24. What is a physical property? List some examples.

• A physical property is a characteristic of matter such as size, shape or phase that can be observed with your senses and measured without changing the identity of the substance. Some examples are color, texture, size, phase, melting point.

25. What is a chemical property? List some examples. • A chemical property is a property of a

single substance that is not easily observed, and describes how the substance REACTS with other matter. Examples are flammability, reactivity,

26. What is the definition of a physical change? List some

examples.• A physical change is when a substance

undergoes a change in some properties but keeps MOST of its properties, and does NOT create a new substance. Examples: cutting paper, breaking a mirror.

27. What is the definition of a chemical change? List some

examples.• In a chemical change, a NEW substance

is created, two separate substances combine and rearrange their atoms. The new substance will have DIFFERENT properties. Examples are burning wood, spoiled milk.

28. What are four hints or ways you know that a chemical

change has occurred?

• Four hints that a chemical change has occurred are: color change, precipitate formed, bubbles, an energy change.

29. Are phase changes physical or chemical changes? Why?

• Phase changes are physical because it is still the same substance, just more or less tightly packed, molecules moving faster or slower.