Using a more concentrated HCl solution and Crushing the CaCO₃ into a fine powder makes the reaction to occur at a faster rate.
<u>Explanation:</u>
CaCO₃(s) + 2HCl(aq) → CaCl₂(aq) + H₂O(aq) + CO₂(g)
When calcium carbonate reacts with hydrochloric acid, it gives out carbon-dioxide in the form of bubbles and there is a formation of calcium chloride in aqueous medium.
The rate of the reaction can be increased by
- Using a more concentrated HCl solution
- Crushing the CaCO₃ into a fine powder
When concentrated acid is used instead of dilute acid then the reaction will occur at a faster rate.
When CaCO₃ is crushed into a fine powder then the surface area will increases thereby increasing the rate of the reaction.
Answer is: concentration of ammonium ions are 7,14·10⁻¹⁴ M.
Chemical reaction: 2NH₃(l) → NH₄⁺(am) + NH₂⁻(am).
Kam = 5,1·10⁻²⁷.
[NH₄⁺] · [NH₂⁻] = x; equilibrium concentration of cations and anions.
Kam = [NH₄⁺] · [NH₂⁻].
Kam = x².
x = [NH₄⁺] = √5,1·10⁻²⁷.
[NH₄⁺] = 7,14·10⁻¹⁴ M.
I believe the answer is sugar crystals with stirring at 15 degrees Celsius.
Solubility is the maximum amount of a substance that will dissolve in a given amount of solvent at a specific temperature. There are two major factors that affect solubility are temperature and pressure. Temperature affects solubility of both solids and gases, but pressure only affects the solubility of gases. Increasing the surface area of solutes also increases the solubility.
A chemical property refers to that which cannot be physically determined. From the choices given above, the chemical property of one of the student's materials is the reactivity of the copper strip. Thus, the answer to this item is letter B.
The Law states that the change in internal energy (U) of the system is equal to the sum of the heat supplied to the system (q) and the work done ON the system (W)
<span>ΔU = q + W </span>
<span>For the first question, 0.653kJ of heat energy is removed from the system (balloon) while 386J of work is done ON the balloon, thus </span>
<span>ΔU = -653J + 386J </span>
<span>=-267J </span>
<span>Thus internal energy decrease by 267J </span>
<span>For the second question, 322J of heat energy is added to the system (gold bar) while no work is done on the gold bar, this is an isochoric/isovolumetric process, thus </span>
<span>ΔU = 322J + 0 </span>
<span>=322J </span>
<span>Thus internal energy increase by 322J</span>
