C. During a storm, a river is carrying a lot more sediment than during a low flow period
Answer:
a) 600 J
b) 75 W
Explanation:
Force= 400 N, distance = 150 cm = 1.5 m, time= 8s
a) Work is the product of force acting on an object and distance (or displacement). The S.I unit of work is the joules.
Work = force × distance = 400 × 1.5 = 600 J
b) Power is the amount of energy transferred per unit time. It is the ratio of work to time. The S.I unit of power is watt
Power = work/time = 600 / 8 = 75 W
Hydrophobic means "water fearing" while polar molecules are hydrophilic meaning "water loving." Hydrophobic exclusion describes the tendency, for examples, of multiple oil droplets in water to coalesce into fewer, larger droplets
Answer : The concentrations of hydroxide and hydronium ions in a solution with a pH of 10.2 are,
and
respectively.
Explanation : Given,
pH = 10.2
pH : It is defined as the negative logarithm of the hydrogen ion concentration.
First we have to calculate the hydrogen ion concentration ![(H^+)](https://tex.z-dn.net/?f=%28H%5E%2B%29)
![pH=-\log [H^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%20%5BH%5E%2B%5D)
Now put the value of pH in this formula, we get the hydrogen ion concentration.
![10.2=-\log [H^+]](https://tex.z-dn.net/?f=10.2%3D-%5Clog%20%5BH%5E%2B%5D)
![[H^+]=6.3\times 10^{-11}](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D6.3%5Ctimes%2010%5E%7B-11%7D)
Now we have to calculate the pOH of the solution.
![pH+pOH=14](https://tex.z-dn.net/?f=pH%2BpOH%3D14)
Now put the value of pH, we get the value of pOH.
![10.2+pOH=14](https://tex.z-dn.net/?f=10.2%2BpOH%3D14)
![pOH=14-10.2](https://tex.z-dn.net/?f=pOH%3D14-10.2)
![pOH=3.8](https://tex.z-dn.net/?f=pOH%3D3.8)
Now we have to calculate the hydroxide ion concentration ![(OH^-)](https://tex.z-dn.net/?f=%28OH%5E-%29)
![pOH=-\log [OH^-]](https://tex.z-dn.net/?f=pOH%3D-%5Clog%20%5BOH%5E-%5D)
Now put the value of pOH in this formula, we get the hydroxide ion concentration.
![3.8=-\log [OH^-]](https://tex.z-dn.net/?f=3.8%3D-%5Clog%20%5BOH%5E-%5D)
![[OH^-]=1.58\times 10^{-4}](https://tex.z-dn.net/?f=%5BOH%5E-%5D%3D1.58%5Ctimes%2010%5E%7B-4%7D)
Therefore, the concentrations of hydroxide and hydronium ions in a solution with a pH of 10.2 are,
and
respectively.
What is the element in which you are trying to find the number of molecules of?