# Search results

1. ### Enthalpy of Formation

Electronegativity is the pull that a certain atom has to attract another atom...i think u can get a better definition from Wikipedia i would really be surprised if the heat of formation had nothing to do with electronegativity, but there mayb another factor, there should be another factor actually
2. ### Enthalpy of Formation

yep....well than it has something to do with internal energy of the elements, but how can the heat of formation be indpendant of electronegativity ?
3. ### Enthalpy of Formation

i think the enthalpy of formation is related to bond strength and attraction between atoms in the formation. but i still don't know what u mean exactly by lattice energy
4. ### Freezing a gallon of water

wel u can say so. but ur considering that the temperature is that of the boundary of the water and not the air (which mayb considered to be that of air in some rare cases, for simplicity), if u want to find that of the air u have to consider air-water convection. 2. u have to pay attention to...
5. ### Freezing a gallon of water

well if it was a H.W they wouldn't have asked u the ambient temperature to freeze this because its another subject. The Q u are finding is the Q needed to move the temperature from a certain temperature to another, in your case you are moving the object from 25 degrees to 0 degrees, the energy...
6. ### Freezing a gallon of water

no 1st trial was correct.. C is the same in Kelvins or Celsius, cause delta T in kelvin or celsius is the same: (sorry i forgot the degrees in C) deltaT in celsius: 25-0 = 25 deltaT in Kelvin: (25+273)-(0+273) = 25...same the first one wass correct
7. ### Freezing a gallon of water

ur welcome..but i have to go,,i'll reply to u as soon as possible. c you around
8. ### Freezing a gallon of water

ok the only way u can go on by this is to add the 2 Q's. then u divide them by the time period u want, and u get the value in kW. the reason we look for the kW value in engineering domains is because in all heat applications we are given the power ratings in kW, like heaters, AC's, heat...
9. ### Freezing a gallon of water

mass is the factor, neither surface area nor volume (well volume through mass anyway). deltaT is the difference of temperature !! its room temperature minus the temperature ur planning to reach which is zero or the freezing temperature. then after that u need to solve how much energy needed to...
10. ### Freezing a gallon of water

yes Q is in Joules, if u divide by the time in the right side of the equation , u get Q in Watts, or J/s translation would be : from T1 to T2 over a certain amount of time needs this much watts to get m is simple : density x volume
11. ### Freezing a gallon of water

since its not a homework : u should apply Q = m c deltaT Q is the heat needed, m is the mass of material, c 4.182 Kj/Kg for pure water, deltaT is your temperature differential..this is the amount ur looking for. physically its possible, but how to do it,well good luck
12. ### Chemical Equilibrium Stresses

woops..i guess you're right. adding an inert gas will have no effect on the concentration of products and reactants..ssorryy
13. ### Chemical Equilibrium Stresses

thus my quote was right ! i was quoting plastic photon who said that adding a nonreactive gas to an equation won't alter its' equilibrium pt.my answer is that it will !
14. ### Chemical Equilibrium Stresses

N2 + 3H2 <--> 2NH3 i meant for this equation sorry. if i increase pressure here i would get the equation shifting towards the right to relieve the pressure right? how do u increase pressure? well u induce a nonreactive gas!! this gas increases the overall pressure in the container thus it...
15. ### Chemical Equilibrium Stresses

ok then. what happens if i increase the pressure in the container without adding or changing anything else?
16. ### Chemical Equilibrium Stresses

Well you are talking about stressing the equilibrium point. if the equation increases pressure if it goes to the right, and you increase the pressure the equation will go towards relieving this pressure and will go to the left. and i'm sure about this answer. And if the equation increases...