Re: 普化考古題 我的答案

[loshihyen (瘦瘦)]

試題 :

1.Provide chemical formulas for the following materials: (10%)
  (1)tin(IV) oxide                          SnO2
  (2)ferrous sulfate                        FeSO4
  (3)sodium crabonate                       Na2CO3
  (4)dinitrogen pentoxide                   N2O5
  (5)hypochlorous acid                      HClO
  (6)hydrochloric acid                      HCl
  (7)ammonium hydroxide                     NH4OH
  (8)lithium perchlorate trihydrate         LiClO4‧3H2O
  (9)thiosulfuric acid                      H2S2O3
  (10)acetic acid                           CH3COOH

2.Fill up the following blank: (10%)
  (1)1 atmosphere=_760_mmHg=_1.013_bar;1 mbar=_0.750_torr.

  (2)A neutral atom of element "X" has 12 eletrons.Its atomic number is _12_,
     with _12_ protons in the nucleus.Its approximate atomic mass is _24amu_.
     Its oxidation state is normally expected tp be _2+_.

  (3)1.5 femtosecond=_1.5E-15_second;0.20 μg= _2E-7_g;9.0 GHz=_9E9_cps.

3.Briefly explain or distinguish the following terms: (20%)

  (1)cathode and anode
     cathode:Electrode at which reduction takes place.
     anode: Electrode at which oxidation takes place.

  (2)homogeneous and heterogeneous mixture
     heterogeneous mixture: Mixture mixed by substances of different phases.
     homogeneous mixture: Mixture mixed by substances of the same phase.

  (3)endothermic and exothermic reation   超出範圍
  (4)enthalpy and entropy                 超出範圍
  (5)extensive and intensive properties   不會
  (6)redox reactions                      超出範圍

  (7)mass number and atomic weight
     mass number: the number of proton + the number of neutron, which is a
                  natural number.
     atomic weight: the actual weight of the atom.  囧

  (8)State function                       超出範圍

  (9)absorption and emission spectra
     The particular patternof wavelengths absorbed and emitted by the atom.

  (10)a quantum and a photon
    quantum: The smallest amount of a physical quantity that can exist
             indipendently, especially a descrete quantity of electromagnetic
             radiation.
    photon: A massless "particle" of light, whose energy is equal to Plank's
            constant times the frequency of the light(hν).

4.For each of the following physical quantities give the order of magnitude
  and dimensions by citing common units: (10%)
  (1)ideal gas constant                 0.082 (atm L/mol K)
  (2)Boltzmann constant                 1.38E-23 (J/K)
  (3)Plank's constant                   6.62E-34 (Js)
  (4)visible lights(in wavelength)      400~700 (nm)
  (5)temperature of liquid nitrogen bath -196 C = 77 K

5.Write the mathematical expressions (5%)
  (1)the Boyles law                             PV=constant

  (2)Dalton's law of partical pressures
     Pi=niRT/V  P=sigma Pi=sigma ni(RT/V)=ntotal(RT/V)

     Xi=ni/ntotal  Pi/P=[ni(RT/V)]/[ntotal(RT/v)]=Xi

     Pi=XiP  P=P1+P2+P3+...=sigma Pi

  (3)Einstein equation for equivalence of mass and energy  E=mc^2

  (4)de Broglie's equation  超出範圍

  (5)Energy levels of Bohr's H-atom
      △E=2.179E-18[(1/n1^2)-(1/n2^2)]  (J)

6.Answer the following quetions: (27%)
  (1)According to the Kinetic Molecular Theory,what is the average
     translational kinetic energy of the gas molecules at constant temperature
     T?  vavg=(8RT/piM)^0.5

  (2)In compared under the same conditions,how much faster than helium does
     hydrogen effuse through a tiny hole?  2^0.5

  (3)What volume of 0.210 M NaOH is required to neutralize 20.0 mL of 0.1050 M
     HCl in an acid-base titration(滴定)?  10.0 (mL)

  (4)Calculate the density of methane gas at 25。C and 1 atm.  0.6548 (g/L)

  (5)How many liters of oxygen gas are consumed for every 10.0 L of CO2(g)
     produced in the combustion of liquid pentane,if all volumes are measured
     at STP?Write the balanced chemical equation for the reaction and do
     calculation.

       C5H12+8O2→5CO2+6H2O,         16.0 (L)

  (6)State the three laws of thermodynamics in words or by using equations.
      (#‵′)凸

  (7)A visible light has a wavelength of 600.0 nm.calculate the frequency and
     the energy.Would it produce the photoeletric effect in potassium? (Given
     the threshold frequency is 5*10^14 Hz)

 ν=c/λ≒5E14 (Hz)   It will produce the photoeletric effect in potassium.

 and E=hν=3.31E-19 (J)

  (8)Explain qualitatively why the endotheric decomposition of calcium
     carbonate to calcium oxide and carbon dioxides is spontaneous at high
     temperature but not at room temperature.

CaCO3→CaO+CO2...超出範圍了吧

  (9)At its normal boiling point,the enthalpy of vaporization of pentadecane
     is 49.45 kJ/mol.What should its approximate normal boiling temperature be
     ?
        超出範圍

7.The three numbers on the fertilizer label are the NPK designation.They
  indicate the nitrogen content expressed as % N,the phosphorus content
  expressed as % P2O5,and the potassium content expressed as % K2O.The use of
  mass percentage based on oxides is a holdover from the way compositions were
  reported in the early days of analytical chemistry.Answer the following
  quetions: (8%)
  (1)What are the percentages of nitrogen,phosphorus and potassium in 5-15-10
     fertilizer?
  (2)What is the NPK designation for pure KH2PO4?
  (3)It is desired to make a 20-20-20 fertilizer using KNO3,NH4NO3,NaH2PO4,and
     an inert ingredient(sand).If this can be done,give the relative mass of
     each of the ingredients present.If this can not be done,show why this is
     the cass.
  Given atomic mass:N,14.00;P,30.97;K,39.10;Na,22.99;O,16.00

        今日頭腦額度已用完...

8.For synthesis of 1 mole ammonia from nitrogen and hydrogen, (10%)
  (1)Write the balanced chemical equation
  (2)Calculate ΔH。,ΔS。,ΔG。 and the equilibrium constant Kp at 25。C by
     using the thermodynamic data given below.
     entropy in J/K: N2(g),191.61;H2(g),130.68;NH3(g),192.45
     enthalpy of formation,ΔHf。[NH3(g)]=-46.11 KJ/mole
  (3)From a thermodynamic point of view,is the reaction spontaneous at 25。C?
  (4)Does high temperature make the reaction more or less spontaneous?

超出範圍

--
          痛啊>"<        ○
               ︵︵\○╱/| 我刀都還沒拿出來你在痛什麼~"~
   . . ﹎ ﹍﹍ ╱￣﹚ ╱＞

--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 218.167.14.158

--
          痛啊>"<        ○
               ︵︵\○╱/| 我刀都還沒拿出來你在痛什麼~"~
   . . ﹎ ﹍﹍ ╱￣﹚ ╱＞

--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 218.167.14.158
※ 編輯: loshihyen       來自: 218.167.14.158       (04/23 18:35)
※ 編輯: loshihyen       來自: 218.167.14.158       (04/23 18:36)
推 ADVANX:第三題的第二小題好像寫反了唷
推 loshihyen:恩 謝謝
※ 編輯: loshihyen       來自: 218.167.14.158       (04/23 20:52)
推 vialeila:二的第三小題...那個cps..是c ps...所以還要再加兩次方
→ vialeila:我是這樣子覺得啦...@@"
推 loshihyen:我查到cycle per second 耶...
推 vialeila:我知道我有錯了@@"我板上有寫呀＝　＝