Answer:
There are 10⁻⁷ hydrogen ions in one-liter water
Step-by-step explanation:
Hi there!
a. If the pH = 7.0, then:
-log(H) = 7.0
multiply both sides of the equation by -1
log(H) = -7.0
Apply 10ˣ to both sides
10^(log (H)) = 10⁻⁷
(H) = 10⁻⁷
There are 10⁻⁷ hydrogen ions in one-liter water.
Why 10^(log (H)) = (H)?
Let´s consider this function:
y = 10^(log x)
(Apply log to both sides)
log y = log 10^(log x)
(Apply logarithmic property: log xᵃ = a · log x)
log y = log x · log 10
(log 10 = 1)
log y = log x
y = x
(since y = 10^(log x) and y = x):
10^(log x) = x
That´s why 10^(log (H)) = (H)
Answer:
(2, - 3 )
Step-by-step explanation:
Given the 2 equations
2x - 3y = 13 → (1)
x + 2y = - 4 → (2)
Rearrange (2) expressing x in terms of y by subtracting 2y from both sides
x = - 4 - 2y → (3)
Substitute x = - 4 - 2y into (1)
2(- 4 - 2y) - 3y = 13 ← distribute and simplify left side
- 8 - 4y - 3y = 13
- 8 - 7y = 13 ( add 8 to both sides )
- 7y = 21 ( divide both sides by - 7 )
y = - 3
Substitute y = - 3 into (3) for corresponding value of x
x = - 4 - 2(- 3) = - 4 + 6 = 2
Solution is (2, - 3 )
Answer:
50.714 (3 dp)
Step-by-step explanation:
Using trigonometry.
Answer:
A,C,F
Step-by-step explanation:
