Answer:
Light years are the only practical unit for measuring the distance of space
Explanation:
Practical... aka logical.
Answer:
Rock to Magma
Explanation:
Lava to Rock is incorrect because its "Freezing" The Lava
Magma to Lava basically a name change. No type change.
Rock to Sediment is Erosion of the rock.
Rock to Magma Is the Rock being super-heated, melting it. Similar to Ice and water but more extreme.
Answer : The hydroxide ion concentration of a solution is, 
Explanation :
As we know that
dissociates in water to give hydrogen ion
and carbonate ion
.
As, 1 mole of
dissociates to give 1 mole of hydrogen ion 
Or, 1 M of
dissociates to give 1 M of hydrogen ion 
So, 0.200 M of
dissociates to give 0.200 M of hydrogen ion 
Now we have to calculate the hydroxide ion concentration.
As we know that:
![[H^+][OH^-]=1\times 10^{-14}](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%5BOH%5E-%5D%3D1%5Ctimes%2010%5E%7B-14%7D)
![0.200\times [OH^-]=1\times 10^{-14}](https://tex.z-dn.net/?f=0.200%5Ctimes%20%5BOH%5E-%5D%3D1%5Ctimes%2010%5E%7B-14%7D)
![[OH^-]=5\times 10^{-14}](https://tex.z-dn.net/?f=%5BOH%5E-%5D%3D5%5Ctimes%2010%5E%7B-14%7D)
Therefore, the hydroxide ion concentration of a solution is, 
Well it matters If it touch with liquid or soild, if touched with liquid it is not call wet, but with soild yes because something dry will get went when touched with water but something wet will stay wet when touched with water.