1. Molarity : 0.25 M
2. mol CH₄ = 7.4 moles
mol O₂ = 14.8 moles
<h3>Further explanation</h3>
1.
Given
83.2 g CuCl2 in 2.5 liters of water
Required
the molarity
Solution
Molarity : mol solute per liter of solution(not per liter of solvent)
mol solute = mol CuCl₂
mol CuCl₂ = mass : MW CuCl₂
mol CuCl₂ = 83.2 : 134.45
mol CuCl₂ = 0.619
Molarity(M) = mol : V
Assume density CuCl₂ = 3.39 g/cm³
volume CuCl₂ = 8.32 g : 3.39 g/cm³ = 2.45 cm³=2.45 x 10⁻³ L
With this small volume value of CuCl₂, the volume of the solute is sometimes neglected in calculating molarity
volume of solution = 2.5 L + 2.45 x 10⁻³ L = 2.50245 L
Molarity(M) = mol : V
M = 0.619 : 2.50245 L = 0.247≈0.25
2.
Given
Reaction
The correct balanced reaction:
CH4 + 2O2 → CO2 + 2H2O
7.4 moles CO2
Required
moles of methane (CH4) and oxygen gas (O2)
Solution
From the equation, mol ratio of CO₂ : CH₄ : O₂ = 1 : 1 : 2
mol CH₄ = mol CO₂ = 7.4 moles
mol O₂ = 2 x mol CO₂ = 2 x 7.4 moles = 14.8 moles
The emission spectrum of an atom consists of limited lines that are unique to a given element.
According to the Bohr model of the atom, energy is absorbed or emitted when an atom moves from one energy level to another. Since energy is quantized, the spectrum of atoms often consists of single lines.
Hence, the true statement about atomic spectrum is that; "the light that an element emits is made up of a limited number of narrow lines that produce a unique pattern or atomic emissions spectrum for that element."
Learn more about atomic spectrum: brainly.com/question/2049494
Below are the choices:
<span>The independent variable is the number of dry cells, and the dependent variable is the length of time the bulb works.
</span><span>The independent variable is the length of time the bulb works, and the dependent variable is the number of dry cells.
</span><span>The independent variable is the number of dry cells, and the dependent variable is the amount of energy available.
</span><span>The independent variable is the amount of energy available, and the dependent variable is the number of dry cells.
</span>
I think the answer is <span>The independent variable is the number of dry cells, and the dependent variable is the amount of energy available.</span>
The correct answer is Reference Point
Answer:
1. watershed
2. point
3. nonpoint
Explanation:
The land that supplies water to a river system is called a watershed
Pollution from a single, identifiable source is called point
Pollution that is difficult to link to a particular origin is called nonpoint