Answer:
In this diagram, the phenomenon moving from medium A which represents water to medium B that represents air is called refraction.
Explanation:
Refraction takes place when light passes through a water surface due to its refractive index which is 1.33. Air possesses a refractive index of about 1. Looking at the phenomenon moving between medium A and B, it seems to bend at the water's surface. This happens because of the bending of the light rays as they move from the water to the air. The time when the rays reach the eyes, the eyes trace them back as straight lines or lines of sight. These lines divide at a higher position than where the actual rays originated. This causes the phenomenon to appear higher and the water to appear shallower than what it is in reality.
Answer is: <span>lumps os sugar dissolving in water.
Sugar has very good solubility in water and it dissolves readily, which is </span><span>example of a physical change.
</span>Gibbs free energy (G) determines if reaction will proceed
spontaneously, if ΔG is negative, reaction is spontaneous <span>(ΔG = ΔH - T·ΔS).
</span>In other examples, reactions are spontaneous in reverse way, for example spontaneous is forming sodium chlorine from sodium metal and chlorine gas, but not sodium chloride forming sodium metal and chlorine gas, because a lot of energy is needed for that reaction.
The number of H atoms in 3(NH₄)₂CrO₄ = 24
<h3>Further explanation </h3>
The empirical formula is the smallest comparison of atoms of compound forming elements.
A molecular formula is a formula that shows the number of atomic elements that make up a compound.
(empirical formula) n = molecular formula
Subscripts in the chemical formula indicate the number of atoms
The compound of 3(NH₄)₂CrO₄ ( 3 molecules of (NH₄)₂CrO₄ ) :
Number of H :
The reaction is properly written as
Mg₃N₂ (s) + 3 H₂O (l) --> 2 NH₃<span> (g) + 3 MgO (s)
Molar mass of Mg</span>₃N₂ = 100.95 g/mol
Molar mass of H₂O = 18 g/mol
Molar mass of MgO = 40.3 g/mol
Moles Mg₃N₂: 3.82/100.95 = 0.0378
Moles H₂O: 7.73/18 = 0.429
Theo H₂O required for available Mg₃N₂: 0.0378*3/1 = 0.1134 mol
Hence, the limiting reactant is Mg₃N₂.
Thus,
Theoretical Yield = 0.0378 mol Mg₃N₂ * 3 mol MgO/Mg₃N₂ * 40.3 g/mol
Theo Yield = 4.57 g
Percent Yield = Actual Yield/Theo Yield * 100
Percent Yield = 3.60 g/4.57 g * 100 =<em> 78.77%</em>
