-Remove goggles when Mr. Leeds says to take them off
-Report all accidents/spills to Mr. Leeds immediately
-Always use common sense
-Fire extinguisher, Fire blanket, and Eye wash/shower
-Never taste chemicals
-Always waft liquids
-Never waft solids or powders
-Don't touch chemicals
-Always wash hands with soap and water after lab
-Flush skin with water if contact with chemicals occurs and notify Mr. Leeds
-Hot and Cold glass look the same
-Never use chipped or broken
-Never use force to remote or insert glass
-Roll up sleeves, put up long hair (not just pull back)
-Never walk away from a lit burner
-Never point the open end of a hot test tube at yourself or someone else
-Don't look down into a test tube/beaker while it is being heated
-Acid into water
-Never add water to acid (could cause an exothermic reaction, water is less dense than acid so it will sit on top of acid and could splash out
-Make sure burner is capped and flame is out
-Clean-up area and materials completely
2. Gather information
3. Form Hypothesis/ Theory
4. Perform experiment
5. Analyze data
Reaction in a Bag
-Substance A and both liquids made the bag hot
-Substance B and both liquids made the bag cold
Chapter 1 Vocabulary
-Inference: a conclusion based upon known observations
-Hypothesis: a proposed solution to a scientific problem
-Control Group: the group that is the standard for comparison in any experiment
-Experimental Group: the group receiving the variable being tested
-Control Factors: the variables that are held constant. They are the same for both the control group and the experimental group.
-Indicator: a substance used to show the presence of another substance.
-Volume: the amount of space something occupies. True of solids, liquids, and gasses.
-Volume Displacement Technique: quick and easy way to determine the volume of a solid or gas.
-Mass: the amount of matter in a substance (true of solids, liquids, and gasses)
-Meniscus: the curved portion of a liquid when in a container. Must read the bottom of the meniscus at eye level for proper measurement.
Heating Baking Soda (1.1)
-Stirring rod is contaminated
-Small hole in the rubber tubing
-Rubber band snapped off
-Stopper not on snuggly
Volume Notes (1.2)
-Volume: L x W x H (A x B x C)
-Standard Unit of Length: meter (m)
-1 Centimeter (1 cm) = .01 m
-100 cm = 1 m
Working With Balances
2. Always "zero" balance before EACH massing
-Push all riders to zero (left)
-Use adjustment knob if needed
3. Never switch pans.
4. Pick up balance by red bar only
5. Return riders to zero when done.
Measuring Volume by Displacement of Water (1.4)
-Sand sticks to side of the cylinder
-Volume of sand and water will be lower
-Crack in funnel
-Pouring water into sand (volume of sand + water up)
-Read level of sand NOT water (volume of sand + water down)
Sensitivity of a Balance (1.8)
The purpose is to discover the sensitivity of your balance. Also, to see if you mass the same object repeatedly will you find the same mass?
1. Zero balance/ clean pan
2. Mass two objects alternately with you partner (penny and a rubber stopper) four times
3. Zero balance before massing each object.
1. Cut a 20 x 20 square out of graph paper
2. Zero balance
3. Mass large square
· Graph paper
· Large stopper
VI. Experimental Errors:
1. The paper I cut out had ink on it so it changed the mass of the paper square.
2. I did not zero the balance and my mass was off.
The purpose is to discover the sensitivity of your balance. Also, to see if you mass the same object repeatedly will you find the same mass? My partner and I each massed two objects, a penny and a stopper. We each did the penny twice and the stopper twice. After that, we compared our results and wrote down each other’s results. We then cut out a paper square that was 20x20. We massed it and got a result of 0.601 g. We then divided by 400 because that’s how many squares were within the 20x20 square. We got a result of 0.0015025 and figured out how many small squares could go into 0.007. We got a result of 4, so we cut out 10 small squares that were 4x4. We then massed the stopper and slowly added the small squares to the pan on the balance. We calculated the results and recorded the results after we added the small squares. The sensitivity of our balance was 0.025 g. A balance’s sensitivity could play a major role in massing objects.
The Mass of Dissolved Salt (2.1)
-Cap not on tight: water spills out
-Cleaning pan between Mi + Mf
-Salt spills when pouring into the bottle
-Not enough shakeage
-Cap not dry
-Remove cap before Mf
-Outside bottle is wet
(All lead to decrease in mass)
Mass of Ice and Water (2.4)
Mass of Copper and Sulfur (2.5)
-Rubber sheet not on tight
-Hole in the Rubber Sheet
-Shaking of the tube
-Clean pan between Mi and Mf
The Mass of a Gas (2.6)
-Inside cap is wet
-Don't close cap quickly enough and tight
-Outside bottle wet during Mi
-Water splashes out when gas is released
Property of Object and Property of Substance
Property of Substance -Identifies what the object is made of
Chapter 3 Vocabulary
-Plateau: the flat portion of a graph. Indicates no change in the dependent variable (y-axis)
-Phase Diagram: a graph that shows the changes in state of matter for any substance
-Barometer: used to measure atmosphere air pressure. Contains a column of mercury and a metric scale in two sealed containers.
-Barometric Pressure: air pressure generated by the atmosphere
-Density: mass per unit volume of any substance unit of measurement is g/cm3
Mass and Volume (3.2)
-Remass a cylinder
-Cylinder is wet when massing
-Not enough water in graduated cylinder
-Water splashes out
The Density of Solids (3.5)
-Mixing up cubes
-Measure same side twice
-Can use edge of ruler as beginning of the number and not 0
-Measure rock volume before massing (it will be wet)
-Mix up cubes
The Density of Liquids (3.6)
Purpose: To use density to compare two liquids to see if they are the same substance.
1. Zero/Clean Balance
2. Waft Liquid
3. Mass empty graduated cylinder
4. Fill graduated cylinder with 10 cm3 of liquid
5. Mass graduated cylinder with liquid
6. Pour graduated cylinder into sink
7. Clean up and repeat with other liquid
· Graduated Cylinder
· Liquid A & B
· Little Beaker
1. Leaving liquid inside the graduated cylinder when you do the massing for the empty cylinder.
2. There can be a ring of water on the bottom of the cylinder leaving a ring on the pan that you wipe away. Therefore, your results will be altered.
The purpose of this lab was to use density to compare two liquids to see if they are the same substance. In this lab, we massed the large graduated cylinder by itself both times. Than we filled the cylinders with 10 cm3 of liquid A and liquid B, after that, we massed the cylinder with the liquid inside. When we recorded our data and found out the density, we received the density of 1.15 g/cm3 for liquid A and 1.01 cm3 for liquid B. We then did a histogram and it showed that the two liquids were different from each other because they were separated by a couple of boxes. The class data supported my data because they were all relatively close to my final density. In the end, I conclude that the two liquids are different from each other because the densities are different from each other.
The Density of Gas (3.7)
-Hand not sealed on the bottle (water leaks out) (volume bigger, density smaller)
-Get water in the pan during Mf (mass down and density down)
-Hole in the tubing (volume down, density up)
-Stopper not on tight (volume down, density up)
-Don't put tube in the bottle quick enough (volume down, density up)
-Remove stopper before tubing (volume up, density down)