Unit 2 Flashcards
What is matter
Matter is all the stuff that exists in the universe
How to scientists define matter
In science, matter is defined as anything that has mass and occupies space
What is mass
Mass is a measure of the amount of matter in a substance or an object
What is the basic SI unit of mass
The basic SI unit for mass is the kilogram (kg), but smaller masses may be measured in grams (g)
Mass vs Weight
Mass measures the amount of matter in an object
Weight measures the force of gravity acting on an object
MASS IS NOT WEIGHT
What does volume measure
Volume is a measure of the amount of space that a substance or an object takes up
Name the different units that might be used to measure volume
The basic SI unit for volume is the cubic meter (m3), but smaller volumes may be measured in cm3, and liquids may be measured in liters (L) or milliliters (mL).
Explain how to use the displacement method to find the volume of an irregularly shaped object
- Add water to a measuring container and record the volume.
- Place the object in the water. Record the new volume.
- Subtract the first volume from the second volume. The difference represents the volume of the object.
What is a physical property of matter
Physical properties of matter are properties that can be measured/observed without matter changing to an entirely different substance.
Physical properties are often things you can detect with your senses.
What are some examples of physical properties
Examples of physical properties of matter include melting point, color, hardness, state of matter, odor, and boiling point.
What is a Chemical Property
- Can be measured or observed with a chemical reaction
- Substance is changed into a different substance
What is an extensive physical property
Properties that depend of the AMOUNT of matter present
Examples of extensive physical properties
Mass, Weight, Volume, Length
What is an Intensive physical property
Properties that depend on the TYPE of matter
Examples of intensive physical properties
Color, Odor, Luster,
Malleability
Ductility
Conductivity
Hardness
Melting/Freezing Point
Boiling Point
Density
What is a Physical change
A change in one or more physical properties without any change in the chemical properties
- Can be reversed
Examples of a physical change
Boiling water, Whipping eggs, Dicing vegetables
Why are physical changes often easy to reverse
Because the chemical properties of matter remain the same
Sates of matter
Different phases in which any given type of matter can exist
What are the four states of matter
Solid, Liquid, Gas and Plasma
Which states of matter are most common on Earth
Liquid, Solid and Gas
What type of property is a state of matter
Physical Property
Liquid
Fixed volume, not a fixed shape
Solid
Fixed volume and shape
Gas
No fixed volume or shape
Crystalline Solids
Have particles that are arranged in a regular repeating pattern
Ex. Tabe Salt
Amorphous Solid
Have particles that are arranged more-or-less at random
Ex. cotton candy
Pressure
The amount of force pushing against a given area
What is the kinetic theory of matter
Particles of matter are in constant motion.
What is the relationship between the kinetic energy of partials and the forces of attraction between partials
Particles of solids have the least kinetic energy and particles of gases have the most kinetic energy
Define state of change
- A change of state occurs whenever matter changes from one state to another
- Changes of state are physical changes in matter
- They are reversible changes that do not change matter’s chemical makeup or chemical properties
Process that change matter to a liquid state
Melting, Freezing, Sublimation(solid to gas), Deposition(gas to solid), Condensation, Evaporation
What is a mixture
A mixture is a physical blend of two or more components, each of which retains its own identity and properties in the mixture.
Are mixtures chemically combined
NO
Homogeneous Mixture
A mixture in which the composition is uniform (evenly mixed) throughout the mixture.
Heterogeneous Mixture
A mixture in which the composition is not uniform (not evenly mixed) throughout the mixture
What is a phase
A separate layer of a heterogeneous mixture
Examples of Homogeneous mixtures
Air, Coffee, Apple Juice
Examples of a Heterogeneous Mixture
Vegetable soup, Chocolate Chip Cookie dough, granite
Why is it important to separate materials from a mixture
In a chemical reaction, it is important to isolate the component(s) of interest from all the other materials so they can be further characterized
What are the ways (7) mixtures can be separated
Filtration, Decanting, Distillation, Magnetism, Evaporation, Centrifuge, Chromatography
Filtration
Separation of a mixture’s components through differences in particle size
Decanting
A fancy term for separating two components by pouring
Distillation
Used to separate two liquids based on their differences in boiling points
Magnetism
Used to separate magnetic substances
Evaporation
Removing a liquid to leave a solid behind
Centrifuge
Separates substances of different densities using a fast rotational motion
Chromatography
Separates two substances by using a mobile phase and a stationary phase
What is an element
A pure substance that cannot be broken down into any other substance.
- It is represented on the periodic table by a symbol
Ex. Au is Gold
How many elements naturally occurring elements do we know of
92
When did scientists begin discovering all of the elements
500 years ago
What is an atom
The smallest particle of an element that still has the properties of that element
How are atoms related to elements
All the atoms of an element are like one another and are different from the atoms of all other elements
What are compounds
A unique and pure substance that forms a new substance when two or more elements combine chemically
What is a molecule
A molecule is the smallest particle of a compound that still has the compound’s properties
What is a chemical property
Chemical properties are properties that can be measured or observed only when matter undergoes a change to become an entirely different kind of matter.
Examples of a chemical property
Reactivity and Flammability
Reactivity
The ability of matter to react chemically with other substances
Flammability
The ability of matter to burn
What happens in any chemical change
Occurs whenever matter changes into an entirely different substance with different chemical properties
List 5 signs that a chemical change has occurred
Release of bubbles
Change of color
Produce of an odor
Release in heat or light
Production of loud sounds
Why can chemical changes often not be reversed
Chemical changes result in different substances, they often cannot be undone
- Some chemical changes can be reversed, but only by other chemical changes
What is involved in all chemical reactions
All chemical reactions involve both reactants and products
Reactants
Substances that start a chemical reaction
Products
Substances that are produced in a reaction
How are chemical reactions written
Formula : Reactants —–> Products
How are bonds involved in chemical reactions
Bonds break and reform during chemical reactions
How to reactants change into products during a chemical reaction
Reactants and Products contain the same atoms but they are rearranged during the reaction, so reactants and products are different substances
How can you tell if a change in matter has caused a chemical reaction
Change in color
Change in temp
Formation of gas
Formation of a precipitate
What is a chemical symbol
One or Two letter designation of an element
What are compounds
Combinations of two or more elements
What is a chemical formula
An expression that shows the elements in a compound and the relative proportion of those elements
Where do the names of many elements come from
The Latin name for the element
What is the law of conservation of mass
Matter cannot be created or destroyed
Describe an example of the law of conservation of mass
You could find the mass of a quantity of liquid water. Then you could freeze the water and find the mass of ice. The mass before and after freezing would be the same, showing that mass is conserved when matter changes state.
