Fall Semester Exam Review - Science - 1/18/2023 - 3rd Period

length definition

distance between 2 points

mass definition

amount of matter in an object

volume definition

the amount of space occupied by an object.

length SI units:

meters (m); includes other meters (etc).

mass SI units:

grams (g); includes other grams (etc).

volume SI units:

liters (L); includes other liters (etc).

length equipment:

metric ruler/metric stick

mass equipment:

electronic digital balance

volume equipment:

graduated cylinder (etc).

What piece of equipment would be used to measure volume accurately?

Graduated Cylinder

What question do you ask yourself when finding the independent variable?

“What is being changed in an experiment?”

What question do you ask yourself when finding the dependent variable?

“What is being measured in/during the experiment?”

What are controlled variables?

variables that are kept the same throughout the experiment and never change (etc).

What is the appropriate format for a hypothesis?

an if, then statement. For example, if (this happens) then (this will happen). Etc.

3 types of graphs:

line graph, bar graph, pie chart

When would you use a line graph?

when you want to track changes over short and long periods of time (etc).

When would you use a bar graph?

when you want to show comparisons between categories of data (etc).

When would you use a pie chart?

when you want to display data, information, and/or statistics in a easy to read format (etc).

What does SULTAN stand for?

S-scale, U-units, L-labels, T-title, A-accuracy, N-neatness

Density triangle:

Mass over density and volume

Is a solution heterogeneous or homogeneous?

Homogeneous

Solution Examples:

salt water, sugar water, air

Is an alloy heterogeneous or homogeneous?

homogeneous

Alloy examples:

stainless steel, bronze, brass

Is a colloid heterogeneous or homogeneous?

heterogeneous

Colloid examples:

fog, milk

Is a suspension heterogeneous or homogeneous?

heterogeneous

Suspension examples:

paint, blood, muddy water

Is a mechanical mixture heterogeneous or homogeneous?

heterogeneous

mechanical mixture examples:

chocolate chip cookies, salad, laundry

viscosity definition:

the property of a substance that describes how easily it can poor or how thick it is (etc).

is viscosity physical or chemical?

physical

reactivity with water definition

the property of a substance that describes whether or not it is reactive with water (etc).

is reactivity with water physical or chemical?

chemical

Conductivity definition

the property of a substance that is a measure of its ability to conduct an electric current (etc).

is conductivity physical or chemical?

physical

boiling point definition

the property of a substance that is the temperature at which it transforms from the liquid state into the gas state.

is boiling point physical or chemical?

physical

flammability definition

the property of a substance that describes whether or not it will catch on fire in the presence of oxygen and heat

is flammability physical or chemical?

chemical

malleability definition

the property of a substance that describes its ability to deform under pressure. for example, to be bent or hammered into a thin sheet without breaking.

is malleability physical or chemical?

physical

density definition

the property of a substance that describes how much mass of a substance is contained in a given volume of space of that substance.

is density physical or chemical?

physical

clarity definition

the property of a substance that describes how difficult it is to scratch its surface (etc).

is clarity physical or chemical?

physical

solubility definition

the property of a substance that describes how easily it dissolves when mixed with another substance.

is solubility physical or chemical?

physical

How would you be able to identify if something gas gone under a physical or chemical change?

You would know if something has undergone a chemical change if it changes its composition in the process.

Physical Change Examples:

bending a wire, ice-cube melting, boiling water, etc.

Chemical Change Examples:

burning wood, rotting fruit, exploding fireworks, rusting metal, etc.

What are three signs that a chemical change (or chemical reaction) has taken place?

1. Gas has been produced (look for bubbles), Change in temperature, A precipitate form, Change in color, Energy produced (light, heat)

5 states of matter:

solid, liquid, gas, plasma, Bose-Einstein Condensate

Solid Characteristics:

definite shapes, definite volume, movement = vibrates back and forth while in place.

Liquid Characteristics:

indefinite shape, definite volume, movement = molecules close but move/slide past each other - ability to flow.

Gas Characteristics:

indefinite shapes, indefinite volume, movement = random walk, move in straight line until collide with another particle and change direction (etc).

Tap water is:

a mixture

When a homemade oil and vinegar salad dressing is left standing, it separates into layers. The salad dressing is a:

suspension

Which of the following is not an example of a physical property: density, clarity, flammability, melting point

flammability

Which material is a poor conductor of heat: iron, wood, silver, or copper?

wood

Which action involves a chemical change: making ice cubes, adding sugar to tea, cutting wrapping paper, or cooking oatmeal

cooking oatmeal

a substance that has little tendency to change into other substances is said to have low: reactivity, viscosity, density, or conductivity

reactivity

Formation of precipitate is usually evidence of: the separation of a mixture, a chemical change, the formation of mixture, or a physical change

a chemical change

Which state of matter has a definite volume, but a variable shape? Solid, liquid, gas, or vapor?

liquid

Which statement is true about the atoms in Helium gas: they travel in circular paths, they have strong attractions to each other, they are not closely packed, or they are arranged in an orderly pattern

they are not closely packed

if the speed of an object increases, its kinetic energy:

increases

\

Phase Change Diagram

What is pressure?

a result of a force distributed over an area

What units do we use to measure pressure?

Pascals (Pa)

What are factors that affect pressure?

temperature, volume, and number of particles

Elements to the left of the staircase

Metals

Elements to the right of the staircase

Non-Metals

An atom must have 8 valence electrons to be stable

Octet Rule

Which of the following is an example of a chemical change? Boiling, burning, evaporation, or melting

burning

How would you classify the color of a rose? chemical change, chemical property, physical change, or physical property?

physical property

How would you describe the process of evaporating water from seawater? Physical change, physical property, chemical change, or chemical property

physical change and physical property

Which of the following is a pure substance? colloid, suspension, solution, or element

solution

Boiling points and freezing points are examples of: chemical properties, physical properties, energy, or matter

physical properties

The particles that make up a solid move __________ than the particles that make up a gas.

slower

Dew collects on a spider web in the early morning.  This is an example of:

condensation

The phase change that is the reverse of vaporization is:

condensation

A helium filled balloon will float in air because:

helium is less dense than air (think of above or below 1 and density, etc).

Almost all of the mass of an atom is located in its:

nucleus

Do groups or periods have similar properties (with elements)?

groups

The group 17 elements are also known as:

halogens

In a modern periodic table, elements are arranged in order of:

atomic number

An element that is brittle and a poor conductor is likely to be a:

nonmetal

Elements that have the same number of electrons in their outer shell are:

in the same group

The ___________________ are numbers found on the lower right-hand side of an element symbol.

subscript

All of the atoms of the elements in Period 2 have the same number of:

occupied energy shells

Which family or group is the least reactive family or group?

noble gases

What is the erlenmeyer flask used for?

mixing chemicals

Pure Substance

Made up of the same type of particle. Examples: Elements and Compounds

Element

made up of only one type of atom

Compounds

Made up of two or more different atoms that are combined in fixed proportions.

Diatomic molecule

Two of the same atoms bonded together for stability. Think BrINClHOF

homogeneous mixture

A mixture in which substances are uniformly distributed throughout the mixture

heterogeneous mixture

A mixture that is not uniform in composition; components are not evenly distributed throughout the mixture

Solution

a homogeneous mixture of two or more substances uniformly dispersed throughout and look like a single phase

Suspension

Type of heterogeneous mixture that separates into layers over time