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23 Cards in this Set
- Front
- Back
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Hess' Law/Calorimetry materials
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HCl
NaOH NH3 NH4Cl Baking SOda Vinegar gradulated cylinder beaker calorimeter (styrafoam) bunsen burner thermometer |
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First Step in Hess' Law Lab
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find heat capacity of calorimeter by mixing hot water with RT water.
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Second Step
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50 mL of HCl+NaOH record temp every 20 secs for 3 min
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Third
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NH4Cl + NaOH
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Fourth
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NH3 + HCl
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Q-calorimeter =
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-Q - H2O
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Flame Test: K
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lavendar
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Cu
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Green
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Ca
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Orange
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Na
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Yellow
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Sr
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Dark red
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Li
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Pink red
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Materials needed for Qualitative analysis
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unknown samples of chemicals
iodine vinegar phynolphtalein solution NaOH benedict's qualitative solution Isopropyl alcohol solution Water test tubes gradulated cylinder bunsen burner |
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step 1
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add H2O first to test for solubility, take aside three ones that do not dissolve
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step two
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add iodine, look for blue = cornstarch
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three
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add vinegar to the two others, one will react w/ bubbles and that is CaCO3. The one that does not react is CaSO4
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four
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add phenolphthalein to each of the eight ones that were soluble. look for bright pink
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five
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fresh tubes of two w/ pink, add vinegar one w/ bubbles is NaCO3 the one w/out is NaOH.
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six
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go back to six, make fresh, add water and then NaOH. Look for white precipitate. this is MgSO4
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seven
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add drops of benedict and hold over flame. look for orange precipitate - levulose
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eight
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make new tubes of remaining four. add vinegar. one that reacts is sodium bicarbonate
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nine
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fresh tubes, add alcohol, the one that dissolves is boric acid.
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ten
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prepare new and heat over flame. the one that turns brown, smells sweet and melts is sugar, the other is salt.
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