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The number of flashes of firely change w...

The number of flashes of firely change with temperature is as follows:
`|{:(T^(@)C,"Number of flashes/min",T^(@)C,"Number of flashes/min"),(25,7,38,47),(28,10,42,82),(32,20,44,108),(35,31,-,-):}|`
Determine the energy of activation for the chemical reaction that leads to the flsah. `(R= 8.314 Jmol^(-1)K^(-1))`

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To determine the energy of activation (Ea) for the chemical reaction leading to the flashes of fireflies, we can use the Arrhenius equation in its logarithmic form: \[ \log \left( \frac{K_2}{K_1} \right) = \frac{E_a}{2.303 R} \left( \frac{1}{T_1} - \frac{1}{T_2} \right) \] ### Step 1: Identify the data From the provided data, we have: ...
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The rate of reaction triples when temperature changes form 20^(@)C to 50^(@)C . Calculate the energy of activation for the reaction (R= 8.314JK^(-1)mol^(-1)) .

The rate constant of a reaction is 1.5 xx 10^(7)s^(-1) at 50^(@) C and 4.5 xx 10^(7)s^(-1) at 100^(@) C. Calculate the value of activation energy for the reaction (R=8.314 J K^(-1)mol^(-1))

The rate constant for the first order decomposition of a certain reaction is described by the equation log k (s^(-1)) = 14.34 - (1.25 xx 10^(4)K)/(T) (a) What is the energy of activation for the reaction? (b) At what temperature will its half-life period be 256 min ?

The variation of equilibrium constant with temperature is given below : {:("Temperature " , "Equilibrium Constant"),(T_1 = 25^@ C , K_1 = 10 ),(T_2 = 100^@ C , K_2 = 100):} The values of DeltaH^@ , Delta G^@ at T_1 and DeltaG_@ and T_2 (in KJ "mol"^(-1) ) respectively , are close to [use R= 8.314 J k^(-1) " mol"^(-1)]

The chemical reaction between mercuric chloride and potasisum oxalate proceeds as under: 2HgCl_(2) + K_(2)C_(2)O_(4) rarr KCl + 2CO_(2) + Hg_(2)Cl_(2) The mass of Hg_(2)Cl_(2) precipitated form different solutions in a given time at 100^(@)C was as follows: |{:("Experiment number",HgCl_(2) (mol L^(-1)),K_(2)C_(2)O_(4) (mol L^(-1)),"Time (min)",Hg_(2)Cl_(2) "precipitated (mole)"),(1,0.0836,0.404,65,0.0068),(2,0.0836,0.202,120,0.0031),(3,0.0418,0.404,60,0.0032):}| form the data calculate order of the reaction.

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Oxygen is of vital importance for all of us . Oxygen enters the body via the lungs and is transported to the tissues in our body by blood . There it can deliver energy by the oxidation of sugars. C_(6)H_(12)O_(6) + 6O_(2) rarr 6CO_(2) + 6H_(2)O This reaction releases 400 KJ of energy per mole of oxygen O_(2) uptake by blood is at four heme (Hm) group in this protein hemoglobin (Hb). Free Hm consists of an Fe^(2+) giving HmO_(2) complex. Carbon monoxides can be complexed similarily giving a Hm CO complex . CO is poison as it bonds more strongly to Hm than O_(2) does. The equilibrium constant K_(f) for the reaction: Hm+ CO hArr HCO " "........(i) is 1000 times larger than the equilibrium constant K_(2) for the reaction: Hm + CO_(2) hArr HmO_(2)" " ........(ii) Each Hb molecules can take up four molecules of O_(2) absorbs a fraction of this amount, depending on the oxygen pressure , as shown in figure1 (curve 1) . Also shown are the curve (2) and (3) for blood with two kinds of dificient Hb . These occur in patients with certain hereditary diseases. Relevant data , O_(2) pressure in lungs is 15 KPa , in the muscles it is 2KPa . The maximum flow of blood through heart and lungs is 4 xx 10^(-4)m^(-3)s^(-1) . The red cells in blood occupy 40% of the volume, inside the cells the concentration of Hb has a molar mass of 64 kg "mol"^(-1) R=8.314 J "mol"^(-1) K^(-1) , T=298k . Using the relation between K and the standard Gibbs energy DeltaG^(@) for a reaction, calculated the difference between the DeltaG^(@) values for the home reactions (i) and (ii).

The number of molecules with energy greater than tha threshold enegy for a reaction increases five fold by a rise of temperature from 27^(@)C to 42^(@)C . Its energy of activation in J/mol is ___________. (Take ln5=1.6094,R=8.314" J mol"^(-1)K^(-1) )

A thermocol vessel contains 0.5kg of distilled water at 30^(@)C . A metal coil of area 5 xx 10^(-3) m^(2) , number of turns 100 , mass 0.06 kg and resistance 1.6 Omega is lying horizontally at the bottom of the vessel. A uniform time-varying magnetic field is set up to pass vertically through the coil at time t = 0 . The field is first increased from zero to 0.8 T at a constant rate between 0 and 0.2 s and then decreased to zero at the same rate between 0.2 and 0.4s . the cycle is repeated 12000 times. Make sketches of the current through the coil and the power dissipated in the coil as function of time for the first two cycles. Clearly indicate the magnitude of the quantities on the axes. Assumes that no heat is lost to the vessel or the surroundings. Determine the final tempreture of water under thermal equilibrium. Specific heat of metal = 500 j kg^(-1) K^(-1) and the specific heat of water = 4200 j kg^(-1) K^(-1) . Neglect the inductance of coil.

The rate of reaction increases isgnificantly with increase in temperature. Generally, rate of reactions are doubled for every 10^(@)C rise in temperature. Temperature coefficient gives us an idea about the change in the rate of a reaction for every 10^(@)C change in temperature. "Temperature coefficient" (mu) = ("Rate constant of" (T + 10)^(@)C)/("Rate constant at" T^(@)C) Arrhenius gave an equation which describes aret constant k as a function of temperature k = Ae^(-E_(a)//RT) where k is the rate constant, A is the frequency factor or pre-exponential factor, E_(a) is the activation energy, T is the temperature in kelvin, R is the universal gas constant. Equation when expressed in logarithmic form becomes log k = log A - (E_(a))/(2.303 RT) Activation energies of two reaction are E_(a) and E_(a)' with E_(a) gt E'_(a) . If the temperature of the reacting systems is increased form T_(1) to T_(2) ( k' is rate constant at higher temperature).

CENGAGE CHEMISTRY ENGLISH-CHEMICAL KINETICS-Archives Subjective
  1. The number of flashes of firely change with temperature is as follows:...

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  2. Rate of a reaction A + B rarr Product, is given as a function of diffe...

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  3. A first order reaction is 20% complete in 10 min. Calculate (a) the sp...

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  4. While studying the decompoistion of gaseous N(2)O(5), it is observed t...

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  5. A first order gas reaction has k = 1.5 xx 10^(-6) s^(-1) at 200^(@)C. ...

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  6. A first order reaction is 50% complete in 30 minutes at 27^(@)C and in...

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  7. In a Arrhenius equation for a certain reaction, the values of A and E(...

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  8. The decomposition of N(2)O(5) according to the equation: 2N(2)O(5)(g) ...

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  9. If the rate of decomposition of N 2 ​ O 5 ​ during a certain time...

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  10. The gas phase decompoistion of dimethyl ether follows first order kine...

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  11. A first order reaction A rarr B requires activation energy of 70 kJ mo...

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  12. form the following data for the reaction between A and B, (a) Cal...

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  13. At 380^(@)C, the half-life period for the first order decomposition of...

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  14. The ionization constant of overset(o+)(NH(4)) ion in water is 5.6 xx 1...

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  15. The time required for 10% completion of a first order reaction at 298K...

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  16. The rate constant for the first order decomposition of H(2)O(2) is giv...

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  17. For the equation N(2)O(5)(g)=2NO(2)(g)+(1//2)O(2)(g), calculate the ...

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  18. The rate constant of a reaction is 1.5 xx 10^(7)s^(-1) at 50^(@)C and ...

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  19. The rate constant for an isomerization reaction, A rarr B is 4.5 xx 10...

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  20. An organic reaction is carried out at 500 K. If the same reaction carr...

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  21. The vapour pressure of two miscible liquids (A) and (B) are 300mm of H...

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