science study guide quiz #1
by: annick mitchell september 17, 2013
lab safety :)
- goggels must be kept OVER YOUR EYES until mr. leed says to put them away at the end of the lab. *even if you are done with the lab
- report ALL accidents to mr. leeds imediately.
- try to use your best common sence
- incase of an emergency call 2828
- safety equipment in the class room is
*fire blanket
* eye wash/ shower
- NEVER taste chemicals
- always WAFT liquids to detect odor
- NEVER WAFT SOLIDS OR POWDERS!
- avoid touching chemicals
- always wash hands with soap and water after a lab
- if a chemical touches your skin: flush skin for 1 minuet AND notify mr. leeds
- hot glass and cold glass look the same
- never used chipped or broken glass
- if there is chipped or broken glass tell mr. leeds and through it away in the proper garbage can
- never use force to insert or remove glass
- if you are using an alcohol burner roll up sleves and put hair UP ALL THE WAY (not just a mid pony tail ALL THE WAY UP!)
- never walk away from a lit burner
- never point the hot part of the test tube at your self or anyone else
- never look down into test tube while its being heated
- make sure burner is capped and the flame is out when done
- at the end of each excpirement YOUR AREA MUST BE CLEAN!!! OR ELSE YOU WILL LOOSE POINTS
- make sure burner is out if it was used
- keep goggles on (over your eyes) until mr. leeds says to put them away
reaction in a bag lab :)
- the purpose of the lab was to record the reaction in the bag when you mix the substances.
- there were 6 materials
*substance a and b
* 2 spoons
*graduated cylinder
*red liquid
*ziplock bag
*water
- the saftey in the lab was to wear goggles and wear an apron
- solid A was rocky, hard, white, chalky, clumpy
- solid B was powdery, white, smoth, looked like fresh snow
- the red liquid was oderless, red, transparent,light, liquidy
- when you mix the 3 substances you find that one turns yellow and the other turns pink. after a while "it was all yellow" (Coldplay lol), it turned foamy, one of the chemicals turned really hot and the other started to turn really cold. the bag started to fill with some sort of gas, and that was really cold too. the yelow foamy substances started to almost disapear. one corner of the bag had some pink in it. when we opend the bag it was almost like a baloon poping and all the gas went into the air and went away.
vocab for this lab:
- exothermic: outside heat (hot)
- endothermic: takes heat away (cold)
we found out that substance A is exothermic
and we also found out that B is endothermic
and we also found out that A+B+liquid= gas
- red liquid= phenol red
*used as a ph indecator
*below 7 turns yellow
*above 8 turns pink
- solid A= calciumchloride (calcium + clorine)
*mildley acidic
*very hydrotropic (attracted, and absorbes water)
* used in canned veggies
*electrolyte in sports drinks
*flavored pickels (salty taste)
- solid B= sodium bicarbonate (baking soda)
*not acidic
* uses: baking soda, cat litter, tooth paste, and laundary detergent
1.1 baking soda lab :)
- this lab was done to record the reaction when baking soda is heated
- for the first part you put about 0.5 cm in a dry test tube, and heat it to see what happens. you put an invrted water bottle (in a containter with water) and ruber band it. you then snake a ruber tube into the inverted water bottle. after a while of the baking soda being heated, the water bottle starts to loose air, because it turns into a gas and makes condensation at the top of the test tube.
- for the 2nd part, you take the test tube with the baking soda that you heat, with the baking soda still in it, and you take another test tube with baking soday thats not heated and you mix unsweatened "publix" tea in them and mix them with the baking soda. the teas in the different test tubes become different colors, and dont mix in all the way with the baking soda. the heated tea is a darker color and is transparent, the unheated one is much lighter of a color and a bit cloudy
- control group= unheated test tube
- experimental group= heated test tube
- indicator= tea (showed you that the heated test tube didn't have baking soda anymore)
- variable= something that you want to measure
- independent variable= causes a change in the variable (dependent)
- dependent variable= the color of the tea
- control factors= same type of tea, same amount of tea, same type of baking soda, same type of baking soda, same stirring rod, same test tube
- experimental errors= hole in the tubing (the gas will come out, bottle wont fill up with gas), uncleaned stirring rod (contamination), stopper not snug (gas could come out)
- the amount of baking soda and gas is less (or egual), because the condensation comes from the baking soda. it cannot produce more than its self.
blue dot questions:
- what do you observe at the bottom of the test tube? the baking soda is turning brown, or nothing is happening to it.
- what do you observe near the top of the test tube? there is condensation and its foggy, water dropplets, and it covers from the hot part of glass to the cool part. the "stuff" on the cool part turns into water.
- what do you observe in th einverted bottle? the water is leaving the bottle and it starts to fill up with gas (from the baking soda test tube)
- where do you think the gas came from? the gas came from the heated baking soda
- where did the droplets on the test tube come from? the dropplets came from the gas (condensation)
- describe the color of the liquid in each test tube. the head one looks like apple juice, and is tiransparent, the other (unheated) test tube, is lighter and more cloudy.
- are the 2 white poweders the same substance? what is your evidence? no they are not the same, because the heated test tube is a different color than the unheated test tube. (that you know is baking soda)
box questions:
- why do you think baking soda is used in baking? becuase it release gas when heated, which help dough/ batter to rise and get fluffy (gupcaks, cookies, etc)
1.2 volume notes
- unit of measurement: cm3 (cubic centimeter)
- volume= length x width x hight
- standart unit of lenght= meeter (m)
- 1 centimeter (1cm)= 0.01 m
*centi means 100
- unit cube= a small cube that it 1cm on each edge (one cubic centimeter) (1cm3)
- volume of liquids: use a graduated cylinder to measure volume
*always check the intervals or scale
- units= mililiters (mL) or cm3
*1mL= 1cm3
- read from the bottom of meniscus
unit of measurement
cubic centimeter
volume of liquids
the miniscus
units
mL
single pan balance notes :{)
- check that the pan is clean and dry
- alwaus "zero" balance the pan before EACH massing
*push all ridges to the zero (all the way to the left)
*use adjustment knob if needed
- NEVER switch pans
- pick up balance by red bar only
- do not zero balance when done
annick mitchell
science per. 6 ~ quiz #1 study guide ~ 9-17-13
peace out
in annicks mind this is mr. leeds
science
chemicals
colored pants
make people emotional