Experiment #1waterpipeinitial temperature25°C100°Cfinal temperature28.7°C 28.7°C?T3.7°C-71.3°Cmass125 g60g?T = Tfinal ? Tinitialhave two unknowns for the pipe ? limited heat (c) and q-use water to play itqw = mwcw?Twqw = (125 g) (4.14 J/g*°C)(3.7°C)qw = 1900 Jq is supreme when cleverness is absorbedamount of free null absorbed is equal to the amount of energy releasedqwater = -qpipeqpipe = -1900 Jcpipe = qpipempipe?Tpipecpipe = -1900 J = 0.4 J/ g*°C(60 g) (-71.3°C)metal of the pipe ? Fe (iron)Experiment #2ethanolpipeinitial temperature25°C100°Cfinal temperature31°C31°C?T6°C-69°Cmass125 g60 gwant to find out specific heat of ?ethanol? ? non sure if it is ethanol-or whatever Dr.
Rosenthal said (so its like solve it without face at table)Step #1; use cpipe from experiment #1Step #2 calculate qpipe = mpipecpipe ?TpipeStep #3 ; -qethanol = qpipeStep #4 cethanol = qethanolmethanol -->TethanolNaOH (s)--> NaOH (aq)bottom of the beaker felt hot ? energy is beingness released by the constitution into the surroundingssystem: NaOH (s) Na+(aq) OH-(aq)surroundings: watertemperature of the water is increasing during the licentiousness ? energy is being released by the system and absorbed by the surroundings (water)-means that the kinetic energy of the water increased (kinetic energy is a reflection of temperature)-the chemical potential energy of the system decreased-released potential energy? the ions are spreading apart (the relation back positions of the ions transportd)-any counterchange in potential energy ? called enthalpy change (in this case, exothermic ? energy is released)NaOH (s) ? NaOH (aq)Potential Energy change = enthalpyEnthalpy ? the potential energy change that a system undergoes, reflected by a change in temperature of the surroundings?heat content? (enthalpy) of substances?H ? token for enthalpy ?H = mc?Theat content of the water (surroundings) increases?H is positive for water?H is negative for NaOHConclusions: exothermic chemical reaction (negative ?H for system ? potential energy went down, released by the system)-energy is a product NaOH (s) ? NaOH (aq)...
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