Answer:
Anhydrous calcium chloride dissolves and becomes liquid
Anhydrous copper (ii) sulphate will produce crystal particles
Explanation:
Anhydrous calcium chloride is deliquescent and hence when it is exposed to air, it absorbs water from air. After absorbing water, it dissolves and after some time a pool of clear liquid appears.
Anhydrous copper (ii) sulphate will form crystal structures and the following reaction will takes place
CuSO4 + 5 H20 --> CuSO4.5H2O
Answer: B) 46.7% Si and 53.3% O
Explanation:
To calculate the mass percent of element in a given compound, we use the formula:

Mass of quartz
= 5.05 g
Mass of silicon = 2.36 g
Mass of oxygen = Mass of quartz
- mass of silicon = 5.05g - 2.36 g = 2.69 g


Thus the percentages of silicon and oxygen in quartz are B) 46.7% Si and 53.3% O
Answer:
The stronger electrolyte is the HCl
Explanation:
Stronger electrolyte are the ones, that in water, completely dissociates.
HCl(aq) → H⁺(aq) + Cl⁻(aq)
HCl(aq) + H₂O(l) → H₃O⁺ (aq) + Cl⁻(aq)
Both are acids, they bring protons to medium but the hydrochloric completely dissociates.
HF (aq) + H₂O(l) ⇄ H₃O⁺(aq) + F⁻(aq) Ka
In the dissociation of weak electrolytes, they ionize but at the same time they bond again, so the reaction is always kept in equilibrium.
It is always true that the rate at which a solute dissolves can be increased by grinding. The smaller the solute the easier it will dissolve in the solvent, while other facts play into the rate at which a solute dissolves in a solvent, a major part of this is also how small the solute is. You can think of how rock salt is harder to dissolve in water compared to finely ground salt.
It is sometimes true that as the temperature of a solvent decreases, the solubility of a solute increase. The reason for this is that for liquids and solids as temperature increases the solubility increases but for gasses, as the temperature increases the solubility decreases.
It is always true that stirring a solute when adding it to a solvent should increase the rate of its dissolving. however, this will not increase the amount that is able to be dissolved in the solution.
It is never true that Henry's law states that the solubility of a gas in a liquid is a function of temperature. Henry's law is a gas law that was determined by William Henry in 1803. The law dictates that when in constant temperature the amount of gas that dissolves in a given volume of a liquid is proportional directly to the partial pressure of the gas at equilibrium with the desired liquid. In simpler terms, the solubility of the gas in a certain liquid is proportional to the partial pressure of the gas above the liquid.
It is always true that two liquids that dissolve in each other are miscible. Miscibility is described as the property of liquids and other substances to mix in all proportions and forming homogeneous solutions.