IPS Exam Study Guide

Lab Safety

don't waft powders

nurse extention- 2828

Chapter 1

  • kilogram-2.2

Volume by Displacement of Water Lab

  • Mr. Leeds assigned lab groups different amounts of dry sand to begin the lab so you know that it doesn't matter what you started with, everyone comes to around 40%.

Sensitivity of a balance Lab

  • 0.001-0.003 is too light so the balance won't detect change.

% of Dry Sand that is Air space

  • Volume of Air space over Volume of Dry sand

% of Dry Sand that is Sand

  • Volume of Sand ALone over Volume of Dry sand

Chapter 1 Vocab

  1. Observation- info obtained by the senses often by direct measurement
  2. Inference- a conclusion based upon known observations
  3. Hypothesis- a proposed solution to a scientific problem
  4. Control group- the group that is the standard for comparison in any experiment
  5. Experimental group- the group receiving the variable being tested
  6. Control factors- the variables that are held constant. THey are the same for both the control group and the experimental group
  7. Indicatior- a substance used to show the prescence of another substance
  8. Volume- the amount of space something occupies, true of solids, liquids, and gases.
  9. Volume displacement Technique- quick and easy way to determine the volume of a solid or gas.
  10. Mass- the amount of matter in a substance (True of solids, liquids, and gases)
  11. Meniscus- the curved portion of a liquid when in a container. Must read the bottle of the meniscus at eye level for proper measurement.

Post-Lab Baking Soda/1.1

  • Condensation
  • Hot gas touches cooler surface and turns back to liquid
  • Baking soda= sodium bicarbonate

Experimental Errors:

  • hole in tubing
  • cap burner before removing tubing
  • stopper not on tight
  • stirring rod contamination

1.2 Volume Notes

  • Unit of measurement: cm(cubed)
  • Volume= l x w x h
  • Standard unit of length= meter (m)

1 centimeter= 0.01 m; 100 cm=1m

Volume of Liquids

  • use a graduated cylinder to measure volume
  • Always check the intervals or scale
  • units= milliliters (mL) or cm(cubed)

Single Pan Balance Notes

  1. Check that pan is clean and dry
  2. Always "zero" balance before EACH massing
  3. Never switch pans
  4. Pick up balance by red bar only
  5. Return riders to zero when done

Volume of Rock

  1. Fill cylinder to a known amount (enough to cover object)
  2. Record the water level
  3. Put rock in
  4. Measure liquid Level
  5. Subtract original water level from rock level

Post Lab 1.4

  1. Experimental Errors
  • sand sticks to sides of cylinder (Volume goes down)
  • pour water into sand (Volume goes up)
  • Pour sand too fast --> funnel will overflow
  • Sand sticks to funnel (wet)

1.5 Mass

1 kilogram= 1,000 grams

1 kilogram= 2.2 pounds

Post Lab 1.8

  1. Experimental Errors:
  • not zeroing the balance
  • cutting unevenly
  • read balance incorrectly
  • pencil marks on paper
  • not estimating to proper place

2. Pennies:

  • Before 1982: 95% copper, 5% zinc
  • After 1982: 2.5% copper, 97.5% zinc

Chapter 2 Vocab

  1. Histogram- a bar graph that shows teh number of times a value is represented for a large sampling group.
  2. Conservation of Mass- In all changes, mass is exactly conserved, provided nothing is added or allowed to escape. Must be a closed system! Not true for volume.
  3. Laws of Nature- Guessed generalization based on many experiments. Can be adjusted when necessary to account for any changes in the limitation of law.

Post Lab 2.1

  1. Why use class data? Saves time, check if calculations are off.
  2. Experimental Errors:
  • Salt spills from the cap into bottle
  • Not drying cap
  • Clean pan between Mi and Mf.

Post Lab 2.4

  1. Condensation comes from warm water vapor touching the cool surface of bottle. (gas to liquid)
  2. Errors:
  • not wiping off condensation on outside
  • ice isn't fully melted
  • shaking bottle
  • cap isn't on tight (evaporation)
  • Not drying bottle and cap
  • Remove cap before Mf

Post Lab 2.5

  1. Errors:
  • Shake test tube
  • Cap flame before reaction ends
  • Rubber sheet not on tightly
  • Hole in rubber sheet
  • Clean pan between massing

Post Lab 2.6

  1. Errors:
  • too much water
  • cap not on tight fast enough
  • bottle wet on outside during Mi
  • cap wet

2. Alka-seltzer

  • sodium-bicarbonate
  • baking soda releases gas

Conservation of Mass Notes

In a closed system, mass will remain constant, regardless of the actions of the processes inside the closed system.

Chapter 3 vocab

  1. Characteristic properties- Properties that show differences between substances. Examples: Desnity, boiling point, solubility, melting point
  2. Plateau- the flat portion of a graph indicates no change in the dependant variable (y-axis)
  3. Phase Diagram- a graph that shows the changes in the substance.
  4. Barometer- used to measure atmospheric air pressure. Contains a column of mercury and a metric scale in a sealed container
  5. Barametric Pressure- air pressure generated by the atmosphere
  6. Density- Mass per unit volume of any substance. Unit of measure is g/cm(cubed)

Post Lab 3.2

Errors:

  • cylinder is wet when massing (mass goes up)
  • re-mass cylinder
  • not enough water in cylinder
  • water splashes out of graduated cylinder

Mass and Volume Notes

  1. Objects that are made of the same substance that have the same volume will have the same mass regardless of their shape
  2. The mass of an object will double if its volume doubles.
  3. Objects that have the same volume but are made of different substances will NOT have the same mass.

3.3 Density

M

--- = D units: g/cm(cubed)

V

Al= aluminum

Post Lab 3.5

  1. Different substances=different densities
  2. Errors:
  • measure volume of rock before massing (mass up, density up)
  • Measure same side of cube/slab
  • mix up the cubes
  • measure from end of ruler, not zero (volume down, density up)

Post Lab 3.6

  1. Errors:
  • liquid sticks to inside walls of cylinder (mass up, density up)
  • contaminated cylinder (wet on inside)
  • dry out cylinder AFTER its massed

2. In the liquids:

  • magnesium sulfate=epsom salt (more in liquid A, higher density)

Post Lab 3.7

Errors:

hand doesn't seal bottle, water leaks out (volume up density down)

remove stopper before tubing

tubing, tablet, stopper (order, volume up, density down)

remove stopper before tubing (volume up, density down)

forget to include foil in Mf (mass up, density down)

touch tablet after Mi (mass up, density up)

stopper not tight, hole in tubing, too long getting tubing into bottle (volume down, density up)

Gas comes from sodium bicarbonate in alka-seltzer (gas is carbon dioxide)