<h3><u>Answer;</u></h3>
1 × 10^-8 M
<h3><u>Explanation</u>;</h3>
pH is given by the -log[H+] while
pOH is given by the -log[OH-]
But;
pH + pOH = 14
Thus; if pH is 6, then pOH = 8
pOH = 8
-log[OH-] = 8
[OH-] = 10^-8 M
The concentration of OH- ions at a pH of 6 is 1 × 10^-8 M
Answer:
D = 9.9 10⁶ mi
Explanation:
In the exercise they give the expression for maximum viewing distance
D = 2 r h + h²
Ask for this distance for a height of 1100 feet
Let's calculate
D = 2 3960 1100 + 1100²
D = 8.712 10⁶ + 1.21 10⁶
D = 9.92 10⁶ mi
D = 9.9 10⁶ mi
Answer : 6.022• 10^23 atoms of potassium
Answer:
λ = 5940 Angstroms
Explanation:
This is an exercise of the relativistic Doppler effect
f’= f √((1- v / c) / (1 + v / c))
Where the speed in between the strr and the observer is positive if they move away
Let's use the relationship
c = λ f
f = c /λ
We replace
c /λ’ = c /λ √ ((1- v / c) / (1 + v / c))
λ = λ’ √ ((1- v / c) / (1 + v / c))
Let's calculate
v = 0.01 c
v = 0.01 3 10⁸
v= 3 10⁶ m / s
λ = 6000 √ [(1- 3 10⁶/3 10⁸) / (1+ 3 10⁶/3 10⁸)]
λ = 6000 √ [0.99 / 1.01]
λ = 5940 Angstroms
