Answer:
A. Gas atoms subjected to electricity emit bright lines of light
Explanation:
When subjected to electricity, the electrons of a gas atom are <em>excited</em>. From that excited energy level, the electrons eventually go back to their initial state; this <u>transition</u> is done by emitting photons at a specific wavelength (causing an emission of bright lines of light).
Such is the mechanism of gas-discharge lamps tipically found in households.
Answer:
-255.4 kJ
Explanation:
The free energy of a reversible reaction can be calculated by:
ΔG = (ΔG° + RTlnQ)*n
Where R is the gas constant (8.314x10⁻³ kJ/mol.K), T is the temperature in K, n is the number of moles of the products (n =1), and Q is the reaction quotient, which is calculated based on the multiplication of partial pressures by the partial pressure of the products elevated by their coefficient divide by the multiplication of the partial pressure of the reactants elevated by their coefficients.
C₂H₂(g) + 2H₂(g) ⇄ C₂H₆(g)
Q = pC₂H₆/[pC₂H₂ * (pH₂)²]
Q = 0.261/[8.58*(3.06)²]
Q = 3.2487x10⁻³
ΔG = -241.2 + 8.314x10⁻³x298*ln(3.2487x10⁻³)
ΔG = -255.4 kJ
Answer: 0.4M
Explanation:
Given that,
Amount of moles of NaOH (n) = ?
Mass of NaOH in grams = 40.0g
For molar mass of NaOH, use the atomic masses: Na = 23g; O = 16g; H = 1g
NaOH = (23g + 16g + 1g)
= 40g/mol
Since, n = mass in grams / molar mass
n = 40.0g / 40.0g/mol
n = 1 mole
Volume of NaOH solution (v) = 2.5 L
Concentration of NaOH solution (c) = ?
Since concentration (c) is obtained by dividing the amount of solute dissolved by the volume of solvent, hence
c = n / v
c = 1 mole / 2.5 L
c = 0.4 mol/L (Concentration in mol/L is the same as Molarity, M)
Thus, the concentration of a solution of a 40.0 g of NaOH in 2.5 L of solution is 0.4 mol/L or 0.4M
Answer:
P.E = 493920 j
Explanation:
Given data:
Mass = 1200 kg
height = 42 m
Potential energy = ?
Solution:
Formula:
<em>P.E = mgh</em>
Now we will put the values in formula.
g = 9.8 m/s²
P.E = 1200 Kg × 9.8 m/s²× 42 m
P.E = 493920 Kg.m²/s²
Kg.m²/s² = j
P.E = 493920 j
The different atmospheric pressures cause the air to have zones with different temperatures, the cold air tends to descend and the hot air to rise because it has less density. This movement of the two airs in the atmosphere is what generates the wind.
