9.96*10⁻²² is the answer, First you find the molar mass of gold, then you turn atoms to moles then moles to grams. There you go you're done!<span />
Answer:
Option 1 is correct.
ΔH for the condensation of 1 kg of Acetone is - 501 KJ.
Explanation:
Molar mass of acetone = 58.08 g/mol
Number of moles of acetone that condenses = mass/molar mass = 1000/58.08 = 17.22 moles
1 mole of Acetone vaporizer with an enthalpy change of 29.1 KJ.
1 mole of Acetone will condense with an enthalpy change of - 29.1 KJ (since condensation is the exact reverse of vaporization)
That is, vaporization is given by,
Acetone(l) ----> Acetone(g) ΔH = 29.1 KJ
Then condensation will be given by,
Acetone(g) ----> Acetone(l) ΔH = -29.1 KJ
So,
1 mole of Acetone will condense with an enthalpy change of - 29.1 KJ
17.22 moles of Acetone will condense with an enthalpy change of 17.22 × - 29.1 KJ = - 501 KJ.
The first option is correct.
Statement 1: The Earth's axis tilt makes one hemisphere face away from the sun during orbit, creating cooler seasons.
Statement 2: The Earth's axis tilt makes one hemisphere face towards the sun during orbit creating warmer seasons.
This is an incomplete question, here is a complete question.
Consider the second-order decomposition of nitroysl chloride:
At 450 K the rate constant is 15.4 atm⁻¹s⁻¹. How much time (in s) is needed for NOCl originally at a partial pressure of 53 torr to decay to 10.6 torr?
Answer : The time needed for NOCl is, 2.52 seconds.
Explanation : Given,
Rate constant = 
Initial partial pressure of NOCl = 56 torr = 0.0737 atm
final partial pressure of NOCl = 14.5 torr = 0.0191 atm
The expression used for second order kinetics is:
![kt=\frac{1}{[A_t]}-\frac{1}{[A_o]}](https://tex.z-dn.net/?f=kt%3D%5Cfrac%7B1%7D%7B%5BA_t%5D%7D-%5Cfrac%7B1%7D%7B%5BA_o%5D%7D)
where,
k = rate constant
t = time
![[A_t]](https://tex.z-dn.net/?f=%5BA_t%5D)
= concentration at time 't'
![[A_o]](https://tex.z-dn.net/?f=%5BA_o%5D)
= initial concentration
As we know that,
Thus, the expression of second order kinetics will be:
As, 
So, 
............(1)
Now put all the given values in the above expression 1, we get:
Therefore, the time needed for NOCl is, 2.52 seconds.
