crhs academic chemistry unit 1 matter and change notes 1 matter... · page 2 of 12 unit 1 notes 1.1...
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Name _____KEY_____________ Period ____
CRHS Academic Chemistry
Unit 1 Matter and Change Notes
Key Dates
Quiz Date _______ Exam Date _______
Lab Dates _______ ________ _______
Notes, Homework, Exam Reviews and Their KEYS located on CRHS Academic Chemistry Website: https://cincochem.pbworks.com
Page 2 of 12 Unit 1 Notes
1.1 MATTER
Definition - Matter is anything that has MASS and takes up SPACE
Chemistry is the science that describes matter, how it changes, and how those changes affect energy. To start, how do we classify matter? By their states (or phases)!
THE STATES (or phases) OF MATTER
Shape? Volume?
Particle Arrangement?
Effect of change in pressure?
Solid
Definite Shape
Definite Volume
Tightly packed particles (moving!) No change
Liq
uid
NO Definite Shape
Definite Volume
(takes shape of container)
Closely packed, but particles glide over one another.
Very Little change
Gas
NO Definite Shape
NO Definite Volume
(fills container)
Loosely arranged particles travel randomly through the container.
Significant amount of change
OK, but WHAT is matter?
ALL matter is composed of __Atoms___________ of chemical elements
An atom is one type of particle in chemistry, and is the smallest unit of an element.
Mass is the amount of ___matter_________________ the object contains.
Regardless of state, ALL MATTER can be divided into 2 groups: Pure_ Substances_____ and Mixtures_________
Unit 1 Notes Page 3 of 12
1. Pure Substances – have a constant composition throughout the sample; contain only ONE type of matter.
o Element – the simplest____________ form of matter and are made of only __one____ type of atom.
The PERIODIC TABLE lists all known elements. Flerovium (114) and Livermorium (116) were added in
2013. Division of the parts of an element is called a nuclear reaction, a topic for another day.
o Compound – __two___ or more elements bound together. Can be divided into simpler substances
only by a chemical reaction (Example: MgCO3 decomposes into MgO and CO2)
2. Mixtures – a physical blend of substances. Contains more than one type of matter; composition may vary.
Can almost always be separated by physical means. Iced tea, ocean water, sand, and steel are examples.
o Homogeneous – appears ___the same_________________ (uniform) throughout. A homogenous
mixture containing a liquid is called a solution (Ex. Salted water)
o Heterogeneous – DO NOT appear uniform. We can easily see different parts of the mixture. (Ex. __Iron
and Sand________)
Mg - ELEMENT
Homogeneous Heterogeneous
CO2 - COMPOUND
Page 4 of 12 Unit 1 Notes
Chemical vs. Physical Properties
A “Property” is a CHARACTERISTIC of a pure substance. They can either be physical or chemical.
1. Physical property – can be observed or measured BUT DOES NOT CHANGE the identity of a material.
a. _Extensive_____ property – depends on the AMOUNT of matter present (mass, length, heat, volume) b. __Intensive_____ property – does NOT depend on the amount of matter present (density, specific heat, melting point, phase)
Matter
Pure Substances
Mixtures
Element
Compound
Homogeneous
Heterogeneous
Carbon (C)
Hydrogen (H)
Gold (Au)
Barium (Ba)
Sodium Chloride (NaCl)
Carbon Dioxide (CO2)
Sand (SiO2)
Hydrchloric Acid (HCl)
Water (H2O)
Paint
Kool Aid
Milk
Vinegar (acetic acid & water)
Steel Gasoline
Cereal & Milk
Salt and Sand
Gravel Granite
EXTENSIVE Depends on AMOUNT of matter
INTENSIVE Does NOT depend on amount of matter
Mass
Volume
Length
Density
Color
Melting Point
Unit 1 Notes Page 5 of 12
Practice: Label property as Intensive (I) or Extensive (E)
Blue Color _I___ Mass _E___Volume _E__ Temperature _I_ Boiling Point _I__ Hardness _I_ Density _I__
2. Chemical property – ability of a substance to undergo a change that changes the identity of the
substance.
Examples: _Flammable; Reacts with; Combustible________________
*Turn to pages 11 to look for properties of hydrochloric acid (HCl) in the Material Safety Data Sheet. MSDS
are available for all chemicals in the lab both in our MSDS binder AND online!
Page 6 of 12 Unit 1 Notes
1.2 DENSITY
Density is an intensive property of pure substances that is a ratio of the mass of an object relative to the
volume of the same object.
𝐷𝑒𝑛𝑠𝑖𝑡𝑦 =𝑀𝑎𝑠𝑠
𝑉𝑜𝑙𝑢𝑚𝑒 𝑑 =
𝑚
𝑣
Units: MASS is measured in metric unit grams (g)
VOLUME is based in either:
i. milliliters (mL)
ii. cubic centimeters (cm3)
1 mL = 1 cm3
Density will be expressed in g/mL OR g/cm3
Example: What is the density of a 114 g mass of lead that has a volume of 10.0 cm3?
𝑑 = 𝑚
𝑣=
114 𝑔
10.0 𝑐𝑚3=
11.4 𝑔
𝑐𝑚3
Units: When mass is in grams (g) and volume is in cubic centimeters (cm3), the units for density are
g/cm3. A cm3 is equal to a mL.
The density of water at room temperature is 1.00 g/cm3. Therefore…
Anything with a density____>_____ than 1.00 g/cm3 will sink in water (Density > water)
Anything with a density ___<_____ than 1.00 g/cm3 will float in water (Density < water)
Example: A cube of ice has a mass of 5 g and a volume of 10 cm3. Will this ice cube float in a glass of
water?
𝑑 = 𝑚
𝑣=
5 𝑔
10 𝑐𝑚3 = 0.5𝑔
𝑐𝑚3 ; Yes the ice cube will float because its density is less than water,
which has density of 1 g/cm3.
Unit 1 Notes Page 7 of 12
Practice: You have a 23.0-g sample of ethanol with a density of 0.7893 g/ml. What volume of ethanol
do you have?
You need to rearrange density equation 𝑫 =𝑴
𝑽 for volume:
Here is one way:
1. 𝑀𝑢𝑙𝑡𝑖𝑝𝑙𝑦 𝑏𝑜𝑡ℎ 𝑠𝑖𝑑𝑒𝑠 𝑜𝑓 𝑑𝑒𝑛𝑖𝑠𝑡𝑦 𝑒𝑞𝑢𝑎𝑡𝑖𝑜𝑛 𝑏𝑦 𝑉 → 𝑉 𝑥 𝐷 = 𝑉 𝑥 𝑀
𝑉 and you are left with
V x D = M because 𝑉
𝑉= 1
2. Then divide both sides of V x D = M by D so that V is by itself on left side of = sign.
𝑉 𝑥 𝐷
𝐷=
𝑀
𝐷 𝑤ℎ𝑖𝑐ℎ 𝑠𝑖𝑚𝑝𝑙𝑖𝑓𝑖𝑒𝑠 𝑡𝑜 𝑉 =
𝑀
𝐷 𝑏𝑒𝑐𝑎𝑢𝑠𝑒
𝐷
𝐷= 1
3. Now plug in given mass (M) = 23.0 g and density (D) = 0.7893 g/mL
𝑉 =23.0 𝑔
0.7893𝑔
𝑚𝐿
= 𝟐𝟗. 𝟏 𝒎𝑳 (3 𝑠𝑖𝑔 𝑓𝑖𝑔𝑠)
Practice: The density of aluminum is 2.7 g/mL. How much mass is there in a 3.0 mL sample of
aluminum?
You need to rearrange density equation 𝑫 =𝑴
𝑽 for mass by multiplying both sides by V:
𝑀 = 𝑉 𝑥 𝐷 = 3.0 𝑚𝐿 𝑥 2.7𝑔
𝑚𝐿
= 𝟖. 𝟏 𝒈 (𝑛𝑜𝑡𝑒 𝑡ℎ𝑎𝑡𝑚𝐿
𝑚𝐿 𝑖𝑠 1 𝑎𝑛𝑑 𝑦𝑜𝑢 𝑎𝑟𝑒 𝑙𝑒𝑓𝑡 𝑤𝑖𝑡ℎ 𝑢𝑛𝑖𝑡𝑠 𝑜𝑓 𝑔 𝑓𝑜𝑟 𝑚𝑎𝑠𝑠)
Practice: A piece of metal with a mass of 147 g is placed in a graduated cylinder. The water level rises from 20.0 mL to 41.0 mL. What is the density of the metal?
𝑉𝑜𝑙𝑢𝑚𝑒 𝑜𝑓 𝑚𝑒𝑡𝑎𝑙 = 𝑇𝑜𝑡𝑎𝑙 𝑉𝑜𝑙𝑢𝑚𝑒 41.0 𝑚𝐿 − 𝐼𝑛𝑖𝑡𝑖𝑎𝑙 𝑉𝑜𝑙𝑢𝑚𝑒 20.0 𝑚𝐿 = 21.0 𝑚𝐿
𝐷 =𝑀
𝑉=
147 𝑔
21.0 𝑚𝐿= 𝟕. 𝟎𝟎
𝒈
𝒎𝑳
Page 8 of 12 Unit 1 Notes
1.3 PHYSICAL vs CHEMICAL “CHANGE” & CONSERVATION OF MASS
Physical change – alters a material without changing its identity.
Examples: __Phase______ change (melting, freezing, sublimating, evaporating, condensing), cutting,
breaking, separating, dissolving
Phase Change Diagram
(Physical Change)
Chemical change – any change in which pure substances are converted into different pure substances with
different characteristic properties. A chemical change means a chemical reaction has occurred.
Examples: __rust, decomposition, synthesis, combustion, replacement___________________
Chemical reactions are accurate and balanced representations of the events of chemical change. We write
them like this:
REACTANT(S) PRODUCT(S)
Reactants – Substances that begin a chemical reaction; written on the LEFT side of the arrow
Products – Substances produced by a chemical reaction; written on the RIGHT side of the arrow
Melting
Boiling Point
Thermal Energy Increases
Temperature Increases
Freezing
Condensation
n
Melting
Boiling Point
or Freezing point!
or Condensation point!
Unit 1 Notes Page 9 of 12
Examples of Chemical Reactions (We study types of chemical reactions in Unit 9)
2H2 + O2 2H2O
2NaCl 2Na + Cl2
2 Li + MgBr2 Mg + 2 LiBr
FOUR Indicators of a chemical change/reaction
1. __Energy or Heat_ exchange (temperature change, emission of light)
2. Change in ___Color____
3. Production of __Gas___ (odor, bubbles)
4. Formation of a precipitate
Precipitate: an insoluble product of a chemical reaction. Usually a solid.
Practice: Label the examples below as physical or chemical changes.
a. _____C_______Iron rusting
b. _____P_______Glass breaking
c. _____C_______Rubbing alcohol catches fire
d. _____P_______Polar ice cap melts
e. _____P_______Glucose dissolving in water
f. _____C_______Bathroom cleaner on lime scale creates small bubbles and the lime scale breaks
down
Page 10 of 12 Unit 1 Notes
Law of the Conservation of Mass
Law of Conservation of Mass in words – Matter cannot be created or destroyed
Law of Conservation of Mass as a formula – In a chemical reaction, the mass of the reactants __Equals___
the mass of the products.
Example: Consider the chemical reaction in which carbon reacts with oxygen to produce carbon dioxide.
What mass of carbon dioxide would be produced if 20.1 grams of carbon reacted completely with 62.5
grams of oxygen?
C + O2 CO2
20.1 g 62.5 g ? The Conservation of Mass law tells us that the total mass on both sides must be equal, so… 20.1 g + 62.5 g = 82.6 g
Practice: When ammonium nitrate (NH4NO3) breaks down explosively, it forms nitrogen gas (N2), oxygen
gas (O2), and water(H2O). When 38 grams of ammonium nitrate explode, 13 grams of nitrogen and 7
grams of oxygen are formed. How many grams of water are formed?
NH4NO3 N2 + O2 + H2O
Practice: Methane (natural gas) is reacted with oxygen in residential furnaces to generate heat during
colder months. The same reaction is used in our laboratory as a common heat source. It takes 500 g of
oxygen to burn 125g of methane completely generating 281 g of water. What mass of carbon dioxide was
also generated?
CH4 + 2O2 CO2 + 2H2O + Heat
18 g
344 g
38g 13g + 7 g + ?
38 = 13 + 7 + X
38 = 20 + X
18 = X
125 g + 500 g X + 281 g + ?
125 + 500 = X + 281
625 = X + 281
625 – 281 = X
344 = X
Unit 1 Notes Page 11 of 12
Material Safety Data Sheet (MSDS) 395.10
SECTION 1 — CHEMICAL PRODUCT / COMPANY IDENTIFICATION
Hydrochloric Acid
Flinn Scientific, Inc. P.O. Box 219 Batavia, IL 60510 (800) 452-1261
SECTION 2 — COMPOSITION, INFORMATION ON INGREDIENTS Hydrochloric acid (7647-01-0)
Synonyms: muriatic acid, toilet bowl cleaners, tile cleaners
CAS# - None established
SECTION 3 — HAZARDS IDENTIFICATION Clear acidic solution. Pungent chlorine odor. Toxic by inhalation and ingestion. Severely corrosive to all body tissues, especially skin and eyes.
Avoid all body contact. Health-2, Flammability-0, Reactivity-2, Exposure-3, Storage-3. 0 is low hazard, 3 is high hazard
SECTION 4 — FIRST AID MEASURES Call a physician and seek medical attention for further treatment, observation, and support after first aid. Inhalation: Remove to fresh air at once. If
breathing has stopped, give artificial respiration immediately. Eye: Immediately flush with fresh water for at least 15 minutes. External: Wash
continuously with fresh water for at least 15 minutes. Internal: Give large quantities of water or milk, followed by a gastric antacid, such as milk of
magnesia. Do not induce vomiting. Call a physician or poison control at once.
SECTION 5 — FIRE FIGHTING MEASURES Nonflammable liquid. When heated to decomposition, emits toxic fumes of HCl and Cl2 or explosive H2 gas. Fire Fighting Instructions: Use a
triclass, dry chemical fire extinguisher. Firefighters should wear PPE and SCBA with full facepiece operated in positive pressure mode.
NFPA CODE: None established.
SECTION 6 — ACCIDENTAL RELEASE MEASURES Restrict unprotected personnel from the area. Remove all ignition sources and ventilate area. Contain the spill with sand or other inert absorbent
material, neutralize with sodium bicarbonate or calcium hydroxide, and deposit in a sealed bag or container. See Sections 8 and 13 for further
information.
SECTION 7 — HANDLING AND STORAGE Flinn Suggested Chemical Storage Pattern: Inorganic #9. Store with inorganic acids.
Store in a dedicated acid cabinet and away from any source of water; if an acid cabinet is not available, store in Flinn Saf-Cube. Use and dispense in
a hood or in a well-ventilated lab only.
SECTION 8 — EXPOSURE CONTROLS, PERSONAL PROTECTION Avoid contact with eyes, skin, and clothing. Wear chemical splash goggles, chemical-resistant gloves, and chemical-resistant apron. Use ventilation
to keep airborne concentrations below exposure limits. Always wear a NIOSH-approved respirator with proper cartridges or a positive pressure, air-
supplied respirator when handling this material in emergency situations (spill or fire).
SECTION 9 — PHYSICAL AND CHEMICAL PROPERTIES Clear fuming liquid with a pungent odor.
Solubility: Soluble in water and alcohol.
Formula: HCl Formula Weight: 36.46 pH < 1
SECTION 10 — STABILITY AND REACTIVITY Avoid contact with (Reacts violently with) strong oxidizers, bases, metals, metal oxides, hydroxides, amines, and other alkaline materials.
Incompatible with cyanides, sulfides, and formaldehyde. Corrodes metal, including steel. Produces heat and may splatter violently when diluted with
water. Shelf Life: Good, if stored safely.
SECTION 11 — TOXICOLOGICAL INFORMATION Acute effects: Poison, corrosive. Chronic effects: Corrosive to teeth. Target organs: Respiratory tract, teeth, skin
SECTION 12 — ECOLOGICAL INFORMATION Does not biodegrade in soil, may be toxic to aquatic life.
SECTION 13 — DISPOSAL CONSIDERATIONS Please consult with state and local regulations. Flinn Suggested Disposal Method #24b is an option.
SECTION 14 — TRANSPORT INFORMATION Shipping Name: Hydrochloric acid
Hazard Class: 8, Corrosive
UN Number: UN1789
SECTION 15 — REGULATORY INFORMATION TSCA-listed, EINECS-listed (231-595-7), RCRA code D002
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