by Isabella Musa
a. If the hight of the space was half the length of an edge of a unit cube, what was the volume of the box?
L x W x H ---- 6 x 5 x 7 x 5= 225 cubic centimeters
b. if the height of the space was 0.47 of the length of an edge of a unit cube, what was the volume of the box?
l x w x h= 6 x 5 x 7 x .47= 224.1 cubic centimeters
2. what is the mass of an iron bar that is 2cm x 4cm x 11cm (1cm of iron has a mass of 7.8)
2 x 4 x 11 x 7.8 ------ 88 x 7.8= 686.4 g
3. a volume of 87 cubic centimeters of dry sand is added to 46 cubic centimeters of water for a total volume of 104 cubic centimeters.
87-58= 29 cubic centimeters
b. what is the volume of the water that doesnt fill the air spaces in the sand
46-41= 5 cubic centimeters
4. to stay physically fit, Mr. Leeds is constatly training. He weighs a trim 178 lbs. What is his weight in kg?
2.2 divided by 178= 81 kg
5. use the following data to find the sensitivity of the balkance used
14.39-14.30=.09 .09/6 (number of yes)
sensitivity of the balance- .02
the bottle wont fill up with gas. therefore they will not come to the conclusion that the baking soda creates the gas.
3 cups of flour- volume
1 tablespoon baking power- volume
11 pound can of pumpkin- mass
1/2 teaspoon vanillia- volume
cinnamon to taste- other
1/2 cup milk- volime
2. A hole in the rubbertubing will result in a gain in mass. this will happen beucase all the gas that is being produced by the heat will escape throught the hole and result in a decrease in mass.
3. condensation on outside of bottle. if you dont wipe off the condensation the water on the outside of the bottle will add onto the orginal mass leading to a result in a gain of mass in the Mf.
2. in all four experiments from chapter 2 the common theme involved investigating changes in mass of different states of matter. you now know that in all the labs there should be no change in mass beucase law of conservation of mass.
3. you are working in a class with no air conditioning and its 90 degrees F. your lab is to take the mass of water (that is 65 degrees f.) in a small plastic bottle with a cap on, then place the bottle in a walk-in freezer allowing the liquid to solidfy, then re-mass the bottle while in the freezer what is a possible error you should be aware of- condensation may form on the outside of the bottle during the Mi and then freeze.
4. a lab group dissolves 2 g of salt into 8 cubic centimeters of water in a beaker with no covoer. after a few days all of the water has evaporate. what will remain in their beaker?
2g of salt
in the density of a gas lab a student forgets to include the foil for the Mf, the result is the mass of the gas increases, and the density decreases.
epsom salt is the marketing name for which chemical compound? magnesium sulfade
For every lab
- must where goggles untill told you can take them off
- report all acciedents ammediately to Mr. Leeds
- use common sense
in case of emergency
- nurse- 2828
Safety equiptment in classroom
- fire extingisher
- fire blanket
- eye wash/shower
- never tase chemicals
- alawsy waft liquids to detect odor
- never waft solids/powders
- avoid touching chemicals
- always wash hands with soap and water after a lab
- if chemicals touch skin: flush skin with water for 1 minute and notify mr. leeds
- hot glass looks the same as cold glass
- never use chipped or broken glass
- dispose of broken glass in the proper bin and tell mr. leeds
- never use force to remove or insert glass
- roll up sleeves and put up hair
- never walk away from a lit burner
- never point the open end of a hot test tube at yourself or someone else
- do not look down into a test tube/beaker while it is being heated
- make sure burner is capped and flame is out when done
End of Experiment
- clean-up area and materials completely
- make certian that burner is out if one was used
- keep goggles on untill mr. leeds says to put them away
Reaction in a Bag
To record the observations that occurs when multiple chemicals substances are combined and to use my observations to understand the reactions of the chemicals.
exothermic reaction- hot
Heating Baking soda
- tube could be broken and would let water out of the bottle and into the container
- the stirring rod could be dirty from a pervious class
- stopper not snug and the gas escapes
control group- unheated test tube
expirimental group- heated test tube
indicator- tea (showed heated test tube was baking soda)
variable- somthing you want to measure
- independent varrible causes a change in the dependent varible
- dependent variable- color of the tea
- control factor- we had control over it-
- same type of tea
- same amount of baking soda
- same amount of tea
- same stiring time
- same size test tube
volume- l x w x h
standard unit of length- meter (m)
1 centimeter (1cm)= .01
volume of liquids
- ise a graduated cylinder to measure volume
- ALWAYS check the intervals or scale
- units- millileters (ml) or cm3
- 1ml= 1cm3
- read rom bottom of the miniscus
Box Questions 1-13 (no #2)
- baking soda is used in baking becuase it relases gas when it is heated which helps dough/batter rise
3. 50 cubic centimeters of water are required to fill a graduated culinder to the 50 ml mark
4. the high or the width of box B is grader than the volume in box A
5. the volume of the stone that was added into the water which made it rise was 7 cm3.
6. a. 8 cubes are needed to build a cube that measures 2 cm along each edege
b. 27 cubes are needed to build a cube that measures 3 cm along each edege
c. 8cm3 is the voluime of the cubes in a. and 27 cm3 is the volume in b.
7. the box measuring 25 cm long, 16 cm wide and 15 cm deep has the larger volume
8. the divisions on the cone are not equally spaced because as the surface increases the depth decreases
9. a. b. c. look at book
10. look at the book
11. see book
13. when the graduated cylinder is narrow and tall the lines are farther apart than when the graduated cylinder in short and wide. this makes the reading easier.