Chemistry Exam Study Guide

9.7023 x 10^-3

0.0097023 in scientific notation:

6.7 kg

2.150 kg + 3.723 kg + 0.8 kg=

0.04176941 m/s Final answer: 0.04177 m/s

25.07 m / 600.2 s =

2814. 50855 kg x m/ s Final answer: 2810 kg x m/ s

287 kg x 9.80665 m/s =

79.433865 kg x m/ s = 79 kg x m/ s

8.1 kg x 9.80665 m/s (Note: 8.1 is the least precise measurement of 2 sig figs)

Metal

A class of elements characterized by physical properties that include shininess, malleability, ductility, and conductivity of heat and electricity; are normally solid Examples: Iron, Lithium, Potassium, Sodium, Calcium, Uranium, Nickel, Copper, Cobalt, Silver, Gold, and Platinum

Physical

A mixture can be separated into pure substances using_______________ processes

change in speed over time m/s/s (Or m/s2)

Acceleration SI Derived Unit:

Tightly packed; mass; volume

Density is a measure of how ______________________molecules or atoms are in a substance. It can be defined as the amount of ______________ per unit______________.

Intensive; does not increase

Density is called an__________________ property, because increasing the amount of the substance_____________________________________ its density.

Base units

Derived units formed by multiplying or dividing_______________________ to measure a different quantity or property in nature.

1.03 atm

Determine the pressure change when a constant volume of gas at 1.00 atm is heated from 20.0 degrees Celsius to 30.0 degrees Celsius.

Precision

Different tools can have differences amounts of ________________________

Length

Distance between two points

4

The measurement, 0.002 060 g, has how many significant digits?

Derived

Units obtained by combining other units

1. Length— l meter (m) 2. Mass— m Kilogram (kg) 3. Temperature— T Kelvin (K) 4. Time— t seconds (s) 5. Number of particles/ Amount of substance — n mole (mol) 6. Luminous Intensity— Candela (cd) 7. Electric Current— Ampere (A)

What are the 7 SI BASE UNITS?

Chemical properties cannot be examined without reacting the sample in some way and observing what happens during the reaction

What can chemical properties cannot be examined without?

A pure substance

What can density be used to identify?

Used to write very large or very small numbers

What is scientific notation used for?

ruler or meter stick

What tool is used to measure Length?

Phase

When a substance changes_______________ (from solid to liquid to gas), the density changes.

Significant digits

When converting a number to scientific notation, scientists only use the _____________________________. If a number is given in scientific notation, it's assumed all digits are significant.

Pressure

When gas molecules collide with the wall of the container, they exert a force on the walls of the container. What is this force called?

375

Write 3.75 x 10^2 in correct standard notation

This is a physical change, because the chalk is staying the same substance, but it is just small dust particles

You volunteer for chalkboard cleaning duty and you get to work with the erasers. As you rub the dust off of the chalkboard, white chalk dust enters the air and makes you cough. As you clean the chalkboard with the eraser, are you causing a physical change or a chemical change?

Metalloids

are solid at room temperature. Have metallic characteristics and nonmetal characteristics Examples: Silicon, Boron, Arsenic. Antimony, Germanium

Kinetic Molecular Theory

based on the idea that particles of matter are always in motion

71 mL

35. mL + 41.1 mL - 5.20 mL =

15.990 cm Final answer: 16.0 cm

7.520 cm 8.2 cm- least precise measurement has one decimal place +0.27 cm ————————

7.051 x 10^6

7051000 in scientific notation:

Mixture

A _______________ is made up of two or more pure substances.

Compound; chemical; molecule

A_________________ is a substance that can be broken down into elements by__________________ processes. The smallest particle of a compound is a __________________ that is made up of two or more types of atoms.

Substance; atoms

After a chemical change, the substance becomes an entirely different__________________(or a mixture of substances). ________________ are rearranged

Uncertainty

All measurements have a degree of ______________.

Mass

Amount of matter in an object

Volume

Amount of space occupied by an object

Element; physical or chemical; atom; molecules

An______________________is a substance that cannot be broken down further by____________________or __________________ processes. The smallest particle of an element is an______________. Some elements normally form__________________ with two or more of the same atom bonded together.

Mixtures

Are made up of two or more different substances; Have physical properties that are different from their components; can be separated into components using physical processes.

Length x another length m2

Area SI Derived Unit:

Last digit; Different

Because the _____________________ is estimated, different people reading the same measurement may produce_____________________ results.

PV= k P1 V1 = P2 V2 (Pressure and Temperature)

Boyle's Law Equation:

V= kT V1/ T1 = V2/ T2 (volume and temperature)

Charles' Law Equation:

chemical structure

Chemical changes are chemical reactions that change the_______________________ of the sample. Substance = new substance

chemical reaction

Chemical properties are properties that can be observed or measured during or right after a _______________________ ___________________

Matter

Chemistry is the study of_______________

1) Move the decimal point to the LEFT, until the coefficient is a number between 1 and 10. Count the number of "jumps", or decimal places you moved. 2) Write the coefficient and " x 10j" where j = number of jumps above

Converting a Large Number to Scientific Notation

1) Move the decimal point to the RIGHT, until the coefficient is a number between 1 and 10. Count the number of "jumps", or decimal places you moved. 2) Write the coefficient and " x 10-j" where j = number of jumps above. Right = reduce

Converting a small number to scientific notation:

Fission

During this reaction, a large unstable isotope is bombarded by high speed particles ( usually neutrons) and breaks apart into smaller particles and nuclei.

Fusion

During this reaction, two smaller nuclei combine together to form a larger nucleus, releasing vast amounts of energy.

unique chemical and physical properties

Each element has

Name; symbol

Elements have a ______________________ ( ex: sodium) and a _________________ ( ex: Na)

Group (Vertical column of the periodic table)

Elements in the same__________________ tend to have similar chemical properties.

If the true value is 8.24 cm, 8.25 cm is an accurate measurement. 9.37 would not be an accurate measurement.

Example of Accuracy:

8.20cm, 8.21cm, 8.19cm are a group of precise measurements.

Example of Precision:

density; color, hardness, melting and boiling points, and electrical conductivity

Examples of Intensive properties: ______________________- the ratio of mass to volume; a measurement of how tightly packed molecules are in a sample * _________________________________ *_________________, _________________ points ________________________________

-Toxicity -Flammability -Heat of combustion

Examples of chemical properties: *_________________- ability to damage living tissue *_________________- ability to burn *_________________- amount of energy released when burned

Cut into pieces, heat, cool, change shape, Melting butter, tearing paper, crushing a can, freezing water, dissolving koolaid, cutting your hair.

Examples of physical changes:

mass times acceleration kg x m/s2 ( or Newton, N)

Force SI Derived Unit:

P= kT P1/ T1 = P2/ T2 (Pressure and temperature)

Gay- lusaac's Law Equation:

Alkali

Group 1 elements are called _________________metals. Li, Na, K, Rb, and Cs are all very reactive.

Alkaline

Group 2 elements are called _________________ earth metals. They are soft metals that also quite reactive.

Heterogeneous

Have visibly distinguishable (separable) parts

Homogeneous

Have visibly indistinguishable (identical) parts

Both are related because they both measure temperature

How are Celsius degree and Kelvin related?

Use balance to measure mass

How are balance and mass related?

Both measure length

How are kilometer and decimeter related?

They both measure volume

How are liters and cubic centimeters related?

Time is measured in second

How are time and second related?

Gas particles are spread farther apart and move faster than solids or liquids.

How do gases compare with liquids and solids in terms of the distance between their particles ?

1

How many significant figures are in the measurement 2 000 kg?

4 significant figures

How many significant figures does this measurement have: 0.002034

7 significant figures

How many significant figures does this measurement have: 0.1050370

5 significant figures

How many significant figures does this measurement have: 10250.

5 significant figures

How many significant figures does this measurement have: 20,000 cups

3 significant figures

How many significant figures does this measurement have: 310 atoms

3 significant figures

How many significant figures does this measurement have: 7520000

5 significant figures

How many significant figures does this measurement have: 7520600

Scientists can measure a substance's density by measuring its mass and its volume. Density= mass/ volume

How to calculate density?

PV=nRT R is the ideal gas constant and ideal gas law it is the same for all hypothetical ideal gases. R = 0.08206 L*atm/(mol*K)

Ideal Gas Law Equation: PV=nRT

1.8 atm

If I have 5.6 liters of gas in a piston at a pressure of 1.5 atm and compress the gas until its volume is 4.8 L, what will the new pressure inside the piston be?

0.0959 mol

If a scientist has a sample of ammonia (NH volume of 2.15 L at standard temperature and pressure (0.00 C and 1.00 atm), how many moles of methane are in that sample?

Precise; accurate

If a set of measurements is ______________ but not _____________, it is often an indication there is an error in using the measurement tool.

Close

If a set of measurements were precise, the measurements would be ________________together.

Nonmetal

If an element is a liquid that does not conduct heat and electricity and is brittle; can exist as gases and solids; they do not have metallic luster and do not reflect light. Example: Sulfur, Carbon, Phosphorus, Bromine, Iodine, Nitrogen, Oxygen, Fluorine, and Chlorine

Doubles

If the average kinetic energy of a gas sample is doubled, what will happen to the temperature of the gas sample?

Quadruple

If the average kinetic energy of a gas sample is quadrupled, what will happen to the temperature of the gas sample?

Quadruple

If the mass of a molecule stays the same but the velocity is doubled, what would happen to the kinetic energy?

Right

If the number does have a decimal point, start at the left and ignore the zeros until you reach a non-zero digit. Count the digits to the _______ of the insignificant zeros.

Left

If the number does not have a decimal point, start at the right and ignore the zeros until you reach a non-zero digit. Count the digits to the _______ of the insignificant zeros.

Significant

If the number represents a distinct counted number of things (examples: molecules, coffee cups, watches) and is not a measurement from a measuring device, all digits are ______________.

Double

If the velocity of a molecule stays the same but the mass of the molecule doubles, what would happen to the kinetic energy?

In Lab, it is often measured in centimeters (cm). SI unit: meter(m)

In Lab, what is length often measured in? What is its SI unit?

In Lab, it is often measured in grams (g). SI unit: Kilogram (Kg)

In Lab, what is mass often measured in? What is its SI unit?

In Lab, it is often measured in Celsius (degree C). SI unit: Kelvin ( K)

In Lab, what is temperature often measured in? What is its SI unit?

In Lab, it is often measured in Seconds (s). SI unit: Seconds (s)

In Lab, what is time often measured in? What is its SI unit?

In Lab, it is often measured in milliliters( mL). Derived SI unit: Cubic meters (m3)

In Lab, what is volume often measured in? What is its derived SI unit?

Decrease

In general, increasing the temperature of a substance____________________ its density by increasing its volume.

Dalton's Law of Partial Pressures

John Dalton in 1802 published his law that in a mixture of non-reacting gases, the total pressure of the gas sample is equal to the sum of the partial pressures of the individual gases. P total= P gas 1 + P gas 2 + P gas 3

meniscus

Make sure you read the measurement at the bottom of the _______________________

Zero

Make sure you____________ the balance before you add the sample you are measuring!

Density

Mass per unit volume

Ductility

Material's ability to be stretched into a wire

solid, liquid, gas, plasma

Matter can exist in three states:_____________, ____________, _____________,____________, and ___________

Physical; chemical

Matter can undergo_________________and_________________ changes

Physical and Chemical

Matter has_________________ and _______________ properties

Mass and volume

Matter is any substance that has both___________________ and _______________

Mass

Matter is the material of the universe: anything that takes up space and has________________

More dense; less dense; least dense

Most substances are____________________ in their solid state, ___________________ in their liquid state, and ____________________ in their gaseous state.

11 cm3

Multiply the following three numbers and report your answer to the correct number of significant figures: 0.020 cm x 50. cm x 11.1 cm= ?

290mL

On hot days, you may have noticed that potato chips bags seem to "inflate", even though they have not been opened. If I have a 250 mL bag at a temperature of 19 degree Celsius, and I leave it in my car which has a temperature of 60 degrees Celsius, what will the new volume of the bag be?

chemical structure

Physical changes are changes that take place to the form of a substance but do not change the ___________________________of the sample Substance = same substance

chemical structure

Physical properties are properties that can be measured or observed without changing the___________________________ of the sample.

elements or compounds; elements

Pure substances can be___________________or __________________, which are combinations of__________________.

3.5

Round the number 3.46 to 2 significant figures

Nature

SI Base units are the building blocks of all measurements. They are based on standard values in______________________

density column

Scientists can create a liquid column with substances that do not dissolve in one another that have different densities.

One

Scientists only record _________ uncertain digit. Any other uncertain digits are considered unmeaningful and insignificant.

Brittle

Shatters into smaller pieces

irreversible

Some chemical changes are reversible but many are __________________________

Decimal

Sometimes scientists need to indicate that a zero digit is significant. To prevent confusion, they put a ____________ at the end of a number.

1. Gas molecules have negligible volume compared to the volume of the gas 2. Gas molecules don't attract or "stick" to each other or the container. 3. Gas molecules are in constant motion and always move in straight lines until they bump into something. 4. Molecule collisions are elastic - the kinetic energy of each molecule is conserved as they bounce off of each other or the wall of the container. 5. The average kinetic energy of gas molecules is directly proportional to temperature only. If the temperature drops to absolute zero, the molecules stop moving.

State the five basic assumptions of the kinetic-molecular theory.

Decimals places

The answer is written with the same number of__________________________ as the least precise measurement in the calculation

Significant figures

The answer is written with the same number of______________________________ as the number of significant figures in least precise measurement

Temperature or pressure; solids and liquids; very little; Gas

The density of a material can change with changes in _______________________ or _________________. ______________ and _______________ densities change______________________ with temperature or pressure changes. _________________ densities do change more with temperature or pressure changes.

Estimated

The digit after the certain digits is the ________________digit.

Temp (K) = Temp (C) + 273.15

The formula for converting Celsius to kelvin?

Pure substances; mixture (pure substances)

The matter around us can be made of____________________ or ________________________.

3

The measurement, 206 cm, has how many significant figures?

Liquid

The state of matter whose particles are close together and held by intermolecular forces, but the particles have enough energy to move around each other freely; they have a definite volume but can take the shape of the container; they are non compressible

Plasma

The state of matter whose particles are normally neutrally charged. The particles break apart into smaller highly kinetic energy; has no definite shape or volume: is electrically conductive

Gas

The state of matter whose particles are not close together and can move anywhere in the container; have no definite shape or volume. It occupies the whole container where it is confined.

Solid

The state of matter whose particles closely packed together. The forces between particles are strong and they cannot move freely but they can vibrate; have a definite shape and definite volume

Noble gases

These gases are called inert because they rarely react to form compounds with other elements. All are gases at room temperature. Examples: Helium, Neon, Argon, Xenon, Krypton

Ideal Gas Law

To create a law that accounts for all of the others, a scientist Emile Clapyron in 1834 came up with this law. This equation is also called the general gas equation. Equation: PV=nRT

Length/time (m/s)

Velocity( or speed) SI Derived Unit:

length x length x length m3

Volume SI Derived Unit:

kg/m3

What is the SI unit of density?

standard temperature and pressure Standard pressure: 1 atm Standard temperature: 273.15k

What is the STP?

KE= 1/2 x mv2

What is the formula you would use to calculate the kinetic energy of a gas molecule if you're given the mass and the velocity of the molecule?

The average speeds and kinetic energies of gas particles increase with an increase in temperature and decrease with a decrease In temperature

What is the relationship between the temperature, speed, and kinetic energy of gas particles?

graduated cylinder

What tool is used to measure Volume?

stopwatch

What tool is used to measure time?

thermometer

What tool is used to measure to Temperature?

Triple beam balance and Digital scale

What two tools are used to measure the mass?

Last digit

When scientists measure and record their measurement, they state the numbers they know are true and then they estimate the _______________________

Scientists use SI units so they have a common language when they talk to other scientists all over the world.

Why use SI units?

8. x 10^-5 g

Write 0.000 08 g in correct scientific notation.

2.3 x 10^ -8

Write 0.000000023 in correct scientific notation.

It is a physical change, because you are the one cutting the paper and it is still the same substance, but just cut into smaller pieces

You cut a piece of paper into small pieces. Is this a physical or chemical change?

This is a chemical change because the oxygen is dissolving the metal on the nail

You find a nail on the ground in the parking lot, in a small puddle of water. Rust has formed on the outside of the nail. Was this a physical or chemical change?

This is a physical change, because the bubbles exits the liquid , which are gas molecules coming out of the solution they were dissolves in

You get a can of soda from the vending machine and your "friend" maliciously shakes it when you're not looking. You open the can of soda and it fizzes all over your desk, making you regret you had brought it to lab in the first place. Is this a chemical change or a physical change?

This is a physical change, because it changes shape due to its change to a mushy substance; it is still ice cream but it has melted

You pick up an ice cream sandwich from the school cafeteria and you stick it in your hoodie pocket so your hands are free to hand the cash over to the cafeteria work. You run into your chem lab partner on your way to your seat and he tells you your homework is due next period. You forget all about your ice cream until you pull the plastic full of mush out of your pocket later that afternoon. Is a chemical or physical change?

This is a chemical change because when the cars burns the fuel, it is used as energy and you are producing gas in the car

You put gasoline in your car and the car burns the fuel. Is this a chemical change or physical change?

Intensive

____________________ properties are physical properties that do not change with the amount of matter in a sample.

Extensive

______________________ properties are physical properties that change with the amount of matter in the sample

Accuracy

_______________________________ is the degree of a specific value with the true value.

Precision

_________________________in a group of measurements is the degree of agreement among several measurements of the same quantity.

Ideal gas

a hypothetical gas that perfectly fits all the assumptions of the kinetic-molecular theory

Malleability

ability to be hammered or beaten into thin sheets or layers

PV=k4T P1 V1/ T1= P2 V2/ T2 ( volume, pressure, and temperature)

combined gas law equation:

Color change, odor produced, gas produced( bubbles), solid produced (precipitate), light or heat ( energy) produced, Copper reacts with oxygen and turns green, dying your hair, baking bread

examples of chemical changes:

Mass/ volume

examples of extensive properties:

What are the 4 fundamental forces?

gravitational force, electromagnetic force, strong nuclear force, weak nuclear force

Time

interval between two events

Element

is a substance that cannot be broken down further.

Kinetic Energy

is related to the speed it is traveling and the mass of the particle