Answer:
The answer is (H30+) =3,55e-8M and (OH-)=2,82e-7M
Explanation:
We use the formulas:
pH= - log(H30+) and Kwater=(H30+)x(OH-)
pH= - log(H30+) ----< (H30+)= antilog- pH=antilog- 7,45=3,55E-8M
Kwater=(H30+)x(OH-)
(OH-)=Kwater/(H30+)= 1,00e-14/3,55e-8 = 2,82e-7
Answer:
1) The power of Niagara Falls is 1.176 × 10⁹ W
2) The number of 15 W LED light bulbs it could power is 78.4 × 10⁶ light bulbs
Explanation:
1) The Niagara falls water mass flow rate = 2,400,000 kg/s
The height of the fall = 50 meters
The gravitational potential energy = Mass (kg) × height (m) × gravity (9.8 m/s²)
The power = The energy converted per second = Mass flow rate (kg/s) × height (m) × gravity (9.8 m/s²)
Therefore;
The power of Niagara Falls= 2,400,000 kg/s × 50 m ×9.8 m/s²= 1.176 × 10⁹ W
The power of Niagara Falls = 1.176 × 10⁹ W
2) The number, n, of 15 W LED light bulbs it could power is given by the relation;
n × 15 W = 1.176 × 10⁹ W
∴ n = 1.176 × 10⁹ W/(15 W) = 78.4 × 10⁶ light bulbs
The number of 15 W LED light bulbs it could power = 78.4 × 10⁶ light bulbs.
The mass of iron (III) oxide (Fe2O3) : 85.12 g
<h3>Further explanation</h3>
Given
3.20x10²³ formula units
Required
The mass
Solution
1 mole = 6.02.10²³ particles
Can be formulated :
N = n x No
N = number of particles
n = mol
No = 6.02.10²³ = Avogadro's number
mol of Fe₂O₃ :
mass of Fe₂O₃ (MW=160 g/mol)
Purpose
prediction
procedure
data
calculation
conclusion - results etc.
