IPS EXAM
By: Brooke Luckman
Chapter 1
Reaction in a Bag
- Red liquid: Phenol Red
- Used as a PH indicator
- Below 7 turn yellow and above 8 turns pink
2. PH Scale measures acidity from acidic neutral to alkaline
3. Two solids: Calcium Chloride (Calcium and chloride)
- Acidic
- Hydrotropic (Attracted to water)
- Used in canned veggies to keep fresh
- Electrolytes in sports drinks
- Flavor in pickles
- Not acidic
- Uses: baking, toothpaste, laundry detergent
Heating Baking Soda
- Gas leaving the test tube comes from the baking soda
- Condensation comes from the baking soda
- Hot gas touches the cooler top of the test tube and turns to a liquid
- Because the color isn't the same the substances are different
- Control Group: unheated baking soda/tea
- Experimental group: heated baking soda/tea
- Indicator: tea (showed that the heated test tube was not baking soda)
- Variables: a category you measure
- Independent Variable
- something that will cause a change in the dependent
- Temperature
10. Dependent Variable
- Teat color
11. Control factors: things we can control
- Using same type of tea
- Amount of baking soda and tea
- Same size test tube
- Same amount of stirring time
12. Experimental Errors
- Whole in the tubing or glass bend - you won't see gas fill the bottle
- Stopper is not snug - " "
- Not cleaning stirring rod - contaminates
13. Less or same amount of condensation and baking soda because the condensation comes from it and it cannot produce more than itself
Volume Notes
- Unit of measure: cm3 (cubic centimeters)
- Volume Formula: LxWxH
- Standard unit of length: meter (m)
- 1cm = .01 m 100cm=1m
- Unit cube: a small cube 1cm on each edge one cubic centimeter=1 cm3
- Always use a grad. cylinder to measure
- Unit: milliliters (mL) or cm3
- 1mL = 1cm3
Single Pan Balance
- Check that pan is clean and dry
- Always "zero" balance before each massing
- Push all riders to zero (left) and use adjustment knob if needed
- NEVER switch pans
- Pick up balance by red bar only
- DON'T zero balance when done
Beach Sand Lab
- Errors
- Sand Sticks to the sides of the wet cylinder = v. of sand & water would be too low
- Pour water into sand = wanter sits on top of sane b/c air spaces don't allow water to filter down
2. Lab groups used different amounts of sand to show that everyone has the same amount of dry sand to begin with. Approx. 40% of air space
Mass Notes
- Beqa: ancient standard mass used in Egypt. Earliest balance found in Egypt (approx. 7,000 years old)
- Mass: Standard unit is Grams (g)
- 1 Kilogram (kg) = 2.2 pounds (lbs)
- 1kg = 2.2 lbs
Sensitivity of a Balance
- Sensitivity of Balance: the lightest mass that you can expect the balance to detect
- The margin of error
- 0.02
Penny Notes
- Prior 1982- 95% copper 5% zinc
- After 1982- 2.5% copper 97.5% zinc
- 1943
- Made of steel and zinc
- Copper was needed for shell casing (bullets)
- A 1943 copper penny has sold for $82,500
Chapter 2
Mass of Dissolved Salt
- Errors
- Not drying off cap = salt might dissolve in water
- Removing cap before Mf = spillage/leakage
- Not shaking long enough = not dissolved
- Cap not on tightly = spillage/leakage
- Spill salt when pouring into bottle
Ice Ice Baby Lab
- Error
- not wiping the condensation off the bottle will add mass
- Cap not on the bottle tight enough when shaking the bottle = water leaks out - decrease in mass
- Bottle is wet during Mi = mass decrease
The Mass of Copper and Sulfur
- Melting point of copper 1,000 C/2,000 F
- Melting point of sulfur 120 C/235 F
- Yellow smoke = water that was in sulfur to a vapor (gas) and it rises in the test tube
- Glow = copper melting
- When mixture cool - sulfur liquid bonds to copper and forms copper sulfide
- Errors:
- Cleaning pan between Mi and Mf
- Hole in rubber sheet = gas escapes
- Reaction isn't completed
- Sulfur stuck to sides of test tube (doesn't react)
- Rubber sheet not sealed on the test tube = gas escapes
Mass of a Gas
- Lab done a lot to be more accurate because gas is hard to work with
- Errors:
- Ring of water in the pan after Mi = loose mass (start over)
- Cap is wet = will make Alka-Seltzur gas release during Mi = loose mass
- Don't close cap tight enough = lose in mass
- Touch tablet after Mi = chalky; pieces on hand = loose mass
3. Alka-Seltzur: Aspirin, citric acid, sodium bicarbonate
Conservation of Mass
- Capped bottle = closed system = space nothing in, nothing out
- Law of Conservation of Mass: in a closed system mass will remain constant, regardless of the actions of the processes inside the closed system.
- Frozen condensation: frost on the outside of the bottle = add mass
Chapter 3
Characteristic Properties
- Property of an Object: doesn't tell you what it is made of
- Property of a Substance: helps you identify what the object is made out of
Mass and Volume
- Objects that are much of the same substance that have the same volume will have the same mass (regardless of their shape)
- The mass of an object will double if volume doubles
- Objects that have the same volume but are made of different substances will not have the same mass
- Errors
- Not drying off the long cylinder before massing - add mass
- Mix up the long cylinder - lower volume
- Water pops out of cylinder - lower volume
Density of a Solid
- Cube one and the slab are made of the same substance
- Volume is the same
- Object with greater mass has higher density
- The Rock
- All have different densities b/c the rock is formed by many substances being compressed together. Different subs = different densities
5. Errors
- Paint chipped off the object - lower mass
- Find volume of rock before mass - water weight
- Measure the same slide twice
Density of a Liquid
- Errors
- Not rinsing cylinder b/w subs
- Do not re-mass empty cylinder
- Outside of cylinder is wet during first mass
Density of a Gas
- When Alka-Seltzur is mixed with water sodium bicarbonate within the tablet releases carbon dioxide
- If a student forgets to include for foil for the Mf, the result is the mass of a gas decreases, density increases
- Errors
- Spilling water when measuring Volume of bottle
- Not putting foil back on pan for Mf
- Break tablet after Mi
4. If the rubber tubing is inserted incorrectly near the bottom of the bottle less gas will collect in the bottle
Formulas
- S + W - W = Sand alone
- Dry Sand - Sand = Air space
- is/of
- Sand that is air and sand that is sand always equals 100%
- ∆ M/# of Yes' = sensitivity
- Ending mass - initial mass of stopper = ∆ M
- Mf - Mi = ∆
- Density = Mass/Volume
- ∆ = Mass or Volume of a Gas