Molecular chemical equation:
K₂C₂O₄(aq)+Pb(OH)₂(aq) → 2KOH(aq) + PbC₂O₄<span>(s).
Ionic equation:
2K</span>⁺(aq) + C₂O₄²⁻(aq) + Pb²⁺(aq) + 2OH⁻(aq) → 2K⁺(aq) +2OH⁻(aq)+PbC₂O₄(s)
Net ionic eqation:
C₂O₄²⁻(aq) + Pb²⁺(aq) → PbC₂O₄(s).
s is solid, do not dissolve in water, potassiom hydroxide is trong base and dissolves in water.
Answer:
B. NH₃ (l) dissolves in water to form a solution
Explanation:
A solution is a uniform or homogenous mixture of two or more substances. The components of a solution are the solute and solvent. The solute is the substance that is being dissolved in another substance. The solvent is the substance which dissolves the solute.
Mixing the given solutes in water results innthe following:
A. Helium being an inert gas does not dissolve in water at all. Therefore, no solution is formed.
B. Liquid ammonia is very solution in water. When mixed with water, it dissolves in water to form aqueous ammonia solution. Aqueous ammonia is an alkaline solution of ammonia dissolved in water.
C. Silicon (iv) oxide, SiO₂, is a crystalline solid whichnis completely insoluble in water. Mixing it with water does not result in the formation of a solution.
D. Pentane, C₅H₁₂, is a liquid hydrocarbon substance which is insoluble in water. It does not mix with water to form a solution, rather it forms two separate immiscible layers of liquids.
Gamma rays consist of pure energy. Beta particles consist of one electron that is released at high speeds from an unstable nucleus and an alpha particle is a helium nucleus.
We know that Gamma rays consist of pure energy because, during Gamma decay, the atomic and mass numbers remain unchanged. Therefore, only energy is emitted.
Gamma rays are weakly ionising, however, they are strongly penetrating and thick concrete or a few centimetres of aluminium is needed to stop them.
Percentage yield=(actual yield/theoretical yield) x 100%
= (45/50) x 100%
= 90%