Answer:
C. Chemical change
Explanation:
A physical change is where something is changed but it doesnt affect the build up of the chemical. For example, if you broke sticks and threw them on the ground, that would be a physical change because the change is happening to the physical being of the object and not its chemical buildup. However, if you lit those sticks on fire, that would be considered a chemical change because you end up with two substances, ash and the remnants of the stick. A nuclear reaction would result in something blowing up so its not that. And a physical property is like what it looks like or how it smells. Hope I helped you!
Answer:
The forward reaction is exothermic.
Explanation:
- Le Châtelier's principle states that when there is an dynamic equilibrium, and this equilibrium is disturbed by an external factor, the equilibrium will be shifted in the direction that can cancel the effect of the external factor to reattain the equilibrium.
- When the mixture turned darker brown, this means that the reaction is shifted towards the left direction (reactants side).
- The temperature is increased and the reaction shifted to the reverse direction, this means that the forward direction is exothermic.
- Exothermic reaction releases heat and when increasing the temperature, the reaction will be shifted to the reverse direction to suppress the effect of increasing the temperature.
- <em>So the right choice is: The forward reaction is exothermic. </em>
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Answer:
Initial concentration of HI is 5 mol/L.
The concentration of HI after 
is 0.00345 mol/L.
Explanation:
Rate Law: ![k[HI]^2 ](https://tex.z-dn.net/?f=k%5BHI%5D%5E2%0A)
Rate constant of the reaction = k = 
Order of the reaction = 2
Initial rate of reaction = 
Initial concentration of HI =![[A_o]](https://tex.z-dn.net/?f=%5BA_o%5D)
![1.6\times 10^{-7} mol/L s=(6.4\times 10^{-9} L/mol s)[HI]^2](https://tex.z-dn.net/?f=1.6%5Ctimes%2010%5E%7B-7%7D%20mol%2FL%20s%3D%286.4%5Ctimes%2010%5E%7B-9%7D%20L%2Fmol%20s%29%5BHI%5D%5E2)
![[A_o]=5 mol/L](https://tex.z-dn.net/?f=%5BA_o%5D%3D5%20mol%2FL)
Final concentration of HI after t = [A]
t =
Integrated rate law for second order kinetics is given by:
![\frac{1}{[A]}=kt+\frac{1}{[A_o]}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B%5BA%5D%7D%3Dkt%2B%5Cfrac%7B1%7D%7B%5BA_o%5D%7D)
![\frac{1}{[A]}=6.4\times 10^{-9} L/mol s\times 4.53\times 10^{10} s+\frac{1}{[5 mol/L]}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B%5BA%5D%7D%3D6.4%5Ctimes%2010%5E%7B-9%7D%20L%2Fmol%20s%5Ctimes%204.53%5Ctimes%2010%5E%7B10%7D%20s%2B%5Cfrac%7B1%7D%7B%5B5%20mol%2FL%5D%7D)
![[A]=0.00345 mol/L](https://tex.z-dn.net/?f=%5BA%5D%3D0.00345%20mol%2FL)
The concentration of HI after is 0.00345 mol/L.
The number of moles of aluminium that are needed to react completely with 13.2 moles of FeO is 8.8 moles
calculation
2Al + 3FeO → 3aFe +Al2O3
by use of of mole ratio of Al: FeO from equation above = 2:3 the moles of Al is therefore
= 13.2 x 2/3=8.8 moles of Al
Answer:
The movement of heat by convection in the asthenosphere causes the rock of the mantle to slowly move in huge streams. ... As the rock of the asthenosphere moves in different directions, it carries parts of the lithosphere along with it. The lithospheric rock can't stretch, so it breaks into pieces--forming the plates.
Explanation:
