Answer:
ΔH= 3KJ
Explanation:
The total heat absorbed is the total energy in the process, and that is in form of entalpy.
ΔH = q + ΔHvap, where q is the heat necessary for elevate the temperature of dietil ether. Suppose the initial temperature is room temperature (25ºC=298 K), then
q= 10g x2.261 J/gK x(310 K - 298K)= 271.32 J= 0.3 kJ
Then
ΔHvap = 10g C4H10O x (1 mol C4H10O/74.12 g C4H10O) x( 15.7 KJ/ 1 mol C4H10O) = 2.12 KJ
ΔH= 2.5KJ ≈ 3KJ
Answer:
there are N_A, "Avogadro's number" of copper atoms in a 63.55*g mass of copper wire. And N_A, "Avogadro's number" = 6.022xx10^23 individual copper atoms. I look on the Periodic Table, and at Z=29, i.e. copper, the quoted atomic mass is 63.55*g.
Explanation:
Answer:
The volume of air at where the pressure and temperature are 52 kPa, -5.0 ºC is
.
Explanation:
The combined gas equation is,

where,
= initial pressure of gas = 104 kPa
= final pressure of gas = 52 kPa
= initial volume of gas = 
= final volume of gas = ?
= initial temperature of gas = 
= final temperature of gas = 
Now put all the given values in the above equation, we get:


The volume of air at where the pressure and temperature are 52 kPa, -5.0 ºC is
.
Answer:
Half-lives of first order reactions
[A]1/2[A]o=12=e−kt1/2.
ln0.5=−kt.
t1/2=ln2k≈0.693k.