The energy of a photon that would move an electron from level 2 to level 5 : B. 4.8 eV
<h3>Further explanation</h3>
The electron energy at the nth shell can be formulated:
<h3>En = -Rh / n²
</h3>
Rh = constant 2.179.10⁻¹⁸ J
So the electron transfer energy (ΔE)
ΔE = E final- E initial
energy at n=2(level 2) = -5.3 eV
energy at n=5(level 5) = -0.5 eV
So the energy absorbed :
Answer: B.22.4 liters
Explanation:
When we attribute to a certain fixed mass of a given gas a fixed number of molecules. Avogadro considered that the mass of 36g of oxygen at any temperature and pressure would have a fixed number of molecules to which he called 1 mol of molecules. So by definition 1 mole of molecules would have a number of molecules equal to that present in 36 g of oxygen. The occupied volume by one mole of molecules at a given temperature and pressure is called molar volume and consists in 22,4 Liters. The molar volume matches the Avogadro Hypothesis (created in 1811 by Amedeo Avogadro), where equal volumes of different gases, at the same temperature and pressure, have even number of moles.
Answer: The weight/weight % or percent by mass of the solute is 5.41 %.
Explanation:
Mass of the sodium sulfate,w = 9.74 g
Volume of the water = 165 mL
Density of the water = 1 g/mL
Mass of the water =
Mass of the solution, W:
Mass of solute + Mass of solvent =9.47 g + 165 g=174.47 g
The weight/weight % or percent by mass of the solute is 5.41 %.
Answer:
True
Explanation:
Whenever something loses thermal energy, it contracts and becomes smaller.
