Answer:

Explanation:
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In this case, according to the attached solubility chart, it is possible for us to realize that about 88 grams of KNO3 are soluble at 50 °C but just 30 grams are soluble at 20 °C in the same 100 g of water.
In such a way, the crystalized mass of this solute can be calculated by subtracting the mass at 50 °C and the mass at 20 °C:

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Answer:
D. Gases were released to the atmosphere
Explanation:
In accordance to the law of conservation of mass, the total amount of reactants must equate the total amount of products at the end of the reaction because matter can not be lost or created. However, certain changes like gas evolution, formation of precipitate etc. indicates the occurrence of a chemical reaction.
In a chemical reaction, the total mass of the product(s) would be less than the total weight of the reactant(s) because GASES, which constituted part of the mass of the reaction, WERE RELEASED INTO THE ATMOSPHERE. However, if the mass of the gas released can be accounted for, the amount of reactants and products must balance.
E = hc/(lamda)
The lamda symbol is wavelength, which this site does not have. I can represent it with an "x" instead.
Plancks constant, h = 6.626×10^-32 J·s
Speed of light, c = 3.00×10^8 m/s
The energy must be greater than or equal to 1×10^-18 J
1×10^-18 J ≤ (6.626×10^-32 J·s)*(3.0×10^8 m/s) / x
x ≤ (6.626×10^-32 J·s)*(3.0×10^8 m/s) / (1×10^-18 J)
x ≤ 1.99×10^-7 m or 199 nm
The wavelength of light must be greater than or equal to 199 nm
In ionic bonding, atoms SHARE ELECTRONS
Geologists have a rule of thumb: when molten rock cools and solidifies, crystals of compounds with the smallest lattice energies appear at the bottom of the mass because of high power of solubility.
<h3>What is lattice energy? </h3>
The lattice energy is defined as the energy change upon the formation of one mole of crystalline ionic compound from its same constituent ions, that are assumed to be initially in the state of gases. It is also defined as measure of the cohesive forces which bind ionic solids together.
As the lattice energy of the ionic compound increase the solubility of that particular compound decrease. Hence compound which have low lattice energy are more soluble than compound having high lattice energy. When molten rocks cools and solidified, the compound having smallest lattice energy become more soluble than crystals of compound which have large lattice energy. Therefore, crystal of compound with the smallest lattice energy start appearing at the bottom of the mass.
Thus, we concluded that due to high solubility power of compound with low lattice energy appear at the bottom of the mass.
learn more about lattice energy:
brainly.com/question/13169815
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