The enthalpy of fusion of a substance is the energy required to change the state of a substance from solid to liquid at a constant temperature. The enthalpy of fusion for iodine, I₂, will be higher. This is because there are stronger intermolecular forces holding the iodine molecules together. The stronger intermolecular forces arise from the fact that iodine is a much larger molecule, so it has much more electrons resulting in higher Van der Waal's forces. This is also visible in the fact that at room temperature, iodine is a solid while nitrogen is a gas.<span />
Answer:
2K +F₂→ 2KF
Explanation:
When we balance an equation, we are trying to ensure that the number of atoms of each element is the same on both sides of the arrow.
On the left side of the arrow, there is 1 K atom and 2 F atoms. On the right, there is 1 K and 1 F atom.
Since the number of K atoms is currently balanced, balance the number of F atoms.
K +F₂→ 2KF
Now, that the number of F atoms is balanced on both sides, check if the number of K atoms are balanced.
<u>Left</u>
K atoms: 1
F atoms: 2
<u>Right</u>
K atoms: 2
F atoms: 2
The number of K atoms is not balanced.
2K +F₂→ 2KF
<u>Left</u>
K atoms: 2
F atoms: 2
<u>Right</u>
K atoms: 2
F atoms: 2
The equation is now balanced.
A force has both size and direction.
The answer is carbon dioxide
Answer:
297 J
Explanation:
The key to this problem lies with aluminium's specific heat, which as you know tells you how much heat is needed in order to increase the temperature of 1 g of a given substance by 1∘C.
In your case, aluminium is said to have a specific heat of 0.90Jg∘C.
So, what does that tell you?
In order to increase the temperature of 1 g of aluminium by 1∘C, you need to provide it with 0.90 J of heat.
But remember, this is how much you need to provide for every gram of aluminium in order to increase its temperature by 1∘C. So if you wanted to increase the temperature of 10.0 g of aluminium by 1∘C, you'd have to provide it with
1 gram0.90 J+1 gram0.90 J+ ... +1 gram0.90 J10 times=10×0.90 J
However, you don't want to increase the temperature of the sample by 1∘C, you want to increase it by
ΔT=55∘C−22∘C=33∘C
This means that you're going to have to use that much heat for every degree Celsius you want the temperature to change. You can thus say that
1∘C10×0.90 J+1∘C10×0.90 J+ ... +
