Notes Five Tennessee SPI Objectives: 1) SPI Chemical Change Outcomes 2) SPI Elements or Compounds 3) SPI Mixtures or Compounds 4) SPI Atmospheric Composition 5) SPI Density Science CFA 05 Review Five Objectives

5 Key Points About Chemical Reactions: 1) A new substance is created 2) The properties of the new substance are different from the substances that you started with 3) No atoms are created or destroyed in chem reactions  (In other words, no mass is created or destroyed!) 4) Atomic bonds are broken and new bonds are formed  (at the valence electron level) 5) compounds form during chemical reactions SPI Chemical Change Outcomes Notes Science A Chemical Change  Is the result of a chemical reaction  Can not be easily undone or reversed Video Link: Chemical ChangesChemical Changes

Chemical Change Indicators-Memory Trick H: Heat-Heat may be given off (it may get hot) O: Odor/gas-There may be a change in odor (how it smells) P: Pop-It may pop or bang (make a loud noise) E: Explode-It may explode (like fire crackers or dynamite) S: Sound- Noise (snap, crackle, pop, whistle, sizzle, bang, boom) R: Rust- Any form of rust is a slow chemical reaction SPI Chemical Change Outcomes Notes Science Memory Trick H.O.P.E.S.R.

Chemical Change Indicators-Memory Trick F: Foam-It may foam (like vinegar & baking soda) F: Flash-It may flash (like a grenade or gun powder) F: Fizzle-It may fizzle (make a hissing sound like Alka-Seltzer) F: Flame- It may burn (like burning paper or wood) P: Precipitate-It may form a solid substance (called a precipitate) C: Color- It may change color (red to blue, green to orange, etc.) C: Cold- It may become cool or cold C: Corrosion- It may corrode (rust) C: Compounds- It can form a compound G: Gas- Gas may be released (may smell different) SPI Chemical Change Outcomes Science Memory Trick 4FP4CG

Here is an example of a question you might see on a quiz or test. Questions Science Sample Question SPI Chemical Change Outcomes

Here is an example of a question you might see on a quiz or test. Questions Science Sample Question SPI Chemical Change Outcomes

Examples of Elements Notes Science H Na Ca -represents one sodium atom -represents one hydrogen atom -represents one calcium atom The element hydrogen The element sodium The element calcium More About Elements  The chemical symbols for elements always start with one capital letter  These chemical symbols can be followed by one (or more) lower case letters Ex: B, C, N, O, F, etc Ex: He, Li, Be, Mg, etc SPI Elements and Compounds

Notes SPI Elements and Compounds Science What Is a Compound?  The properties of the new substance are different from the substances that you started with.  Chemical formulas for compounds always contain more than one capital letter. …note that it has more than 1 capital letter H2O H2O C 12 H 22 O 11 This is the compound called water This the compound called table sugar  …two or more different elements that are chemically bonded via a chemical reaction to form a new substance.

Is this an element or a compound? Write a capital E if you think it is an element Write a capital C if you think it is a compound Cs (Cesium) Why?...is a pure substance, consists of only one type of atom How to tell?...It only has one capital letter! Element Review Activity SPI Elements and Compounds Science

Is this an element or a compound? Write a capital E if you think it is an element Write a capital C if you think it is a compound NaCl (Sodium Chloride) Why?... Has 2 different types of atoms bonded together How to tell?...It has more than one capital letter! Compound Review Activity SPI Elements and Compounds Science

Here is an example of a question you might see on a quiz or test. Questions Science Sample Question SPI Elements and Compounds

Here is an example of a question you might see on a quiz or test. Questions Science Sample Question SPI Elements and Compounds

 When you combine two or more substances together, if no chemical reaction occurs, then it is called a mixture.  Any changes you observe are only physical changes.  Mixtures can be fairly easily separated back into their parts. What is a Mixture? AirSteelSalt WaterBlood Mixture Examples:  Reminder: compounds CAN NOT be easily separated Milk  No new substances are formed in mixtures. SPI Mixtures or Compounds Soup Soft drinks Salad Tea Pizza HamburgersTacos Kool Aid

Is this a mixture or a compound? Write a capital M if you think it is a mixture. Write a capital C if you think it is a compound. (Glucose) Why?...has 3 atoms chemically bonded together Compound A chemical formula with more than one capital letter is a compound. Review Activity SPI Mixtures or Compounds Science C 6 H 12 O 6

Is this a mixture or a compound? Write a capital M if you think it is a mixture. Write a capital C if you think it is a compound. Why? …The ingredients DO NOT chemically combine Ingredients: Water, chicken, vegetables, noodles, salt, etc. Mixture Review Activity SPI Mixtures or Compounds Science Chicken Soup

Earth's Current Atmosphere …(approx) 78% nitrogen …(approx) 21% oxygen …(approx) 1% other gases (Argon, etc) (argon, water vapor, carbon dioxide, etc) SPI Atmospheric Composition Notes Science Earth's Atmosphere Earth’s atmosphere is a mixture of various gases Nitrogen 7 N 14.0 Oxygen 8 O 16.0 Argon 18 Ar 39.9 Remember! Our atmosphere is a MIXTURE & not a compound

Earth's Current Atmosphere …approx) 1% other gases (Argon etc.) SPI Atmospheric Composition Notes Science Argon (Ar) Neon (Ne) Carbon Dioxide (CO 2 ) Helium (He) Methane (CH 4 ) Water Vapor (H 2 O) …and any other odor, pleasant or unpleasant, that you have ever smelled. What are the “other” gases? Note: They are called Trace Gases

Questions Science SPI Atmospheric Composition

Questions Science SPI Atmospheric Composition Argon Neon Carbon Dioxide Helium Methane Water Vapor Argon and various trace gases make up about 1% of Earth’s atmosphere.

SPI Density Science Notes What is density?  Density is the amount of matter (mass) you have crammed in a given space (volume) Reminder: mass is how much matter is in an object  The unit for mass is grams (mg or g or kg) Reminder: volume is how much space it takes up (size)  Unit for solid volume is cubic meters (cm 3 or m 3 or km 3 )  Unit for liquid volume is liters (mL or L or kL) Density Formula Density = mass divided by volume or D= M V Density = volume mass MVMV D =

Solve the Density Problem Shown Below  Do not use a calculator  Round to the hundredths place  Show all of your work Reminder: The mouse goes in the house (mass is the mouse!) Density = Units… g/cm 3 Answer: 2.5 g/cm ___ Calculate the density of an object with a mass of 25g and a volume of 10cm 3

Solve the Density Problem Shown Below  Do not use a calculator  Round to the tenths place  Show all of your work Reminder: The mouse goes in the house (mass is the mouse!) Density = Units… kg/m 3 Answer: 1.05 kg/m __ 0 -___ Calculate the density of an object with a mass of 45kg and a volume of 43m

Notes Science SPI Density Note: The density formula can be rearranged to find the mass or volume. A) Start with DMV for density B) Move the first letter (D) to the end C) Now you have MVD for mass (think M for multiply!) D) Move the first letter (M) to the end E) Now you have VDM for volume MDMD V= Volume = Density divides Mass or Mass = Volume x Density m = V x D or Density = Mass divided by volume MVMV D= or Memory Trick: DMV to MVD to VDM