Answer: (3) Energy is absorbed as bonds are broken, and energy is released as bonds are formed.
Explanation:
1) The equation given is H₂(g) + Cl₂(g) → 2HCl(g) + energy
2) The energy is shown in the product side, so energy is a product of the reaction, so energy is release.
But this is just the net energy of the process. You need more insight to deal with the energy changes in the reaction.
3) Chemical bonds store energy; this stored energy is the potential chemical energy of the molecules.
When a chemical reaction occurs, the first stage is to brake bonds.
Braking chemical bonds requires energy to overcome the bond energy. Braking bonds always absorbs energy.
On the other hand, forming bonds always release energy.
The neat energy of the reaction is the difference between the energy needed to break bonds and the energy released when new bonds form.
So, regardless the fact that, in the chemical equation that represents the reaction a net energy release is shown, you know that energy is absorbed as bonds are broken, and energy is released as bonds are formed (option 3).
Answer:
Option E
Explanation:
As work is dot product of force and displacement
W=FdCos0
As Cos 0=1 so W=F.d(1)
W=F.d
as Cos 90=0 so no work will be done when angle between force and displacement is 90 degree. At angle between force and displacement is 180 degree then negative value com as Cos 180= -1
Not sure if this is correct but i would choose the steel tray.
You can use the formula M1 x V1 = M2 x V2 where M1 is the molarity of the first substance and V1 is the volume of the substance. M2 is the molarity of the 2nd substance and V2 is the volume of the substance
if substance 1 is HCl and 2 is KOH we can set up the following equation
x moles / liter (unknown) x .02 liters = .5 moles/ liter x .032 liters
x moles / liter x .02 liters = .016 moles
x moles / liter = .016/.02 liters
x moles / liter = .8 moles/ liter
You have . 8M HCL
