Gold is actually very soft. If rings were made of pure gold they would bend and become disfigured. Other elements are added to give the ring its stability.
Answer:
(molecular) 3 CaCl₂(aq) + 2 (NH₄)₃PO₄(aq) ⇄ Ca₃(PO₄)₂(s) + 6 NH₄Cl(aq)
(ionic) 3 Ca²⁺(aq) + 6 Cl⁻(aq) + 6 NH₄⁺(aq) + 2 PO₄³⁻(aq) ⇄ Ca₃(PO₄)₂(s) + 6 NH₄⁺(aq) + 6 Cl⁻(aq)
(net ionic) 3 Ca²⁺(aq) + 2 PO₄³⁻(aq) ⇄ Ca₃(PO₄)₂(s)
Explanation:
The molecular equation includes al the species in the molecular form.
3 CaCl₂(aq) + 2 (NH₄)₃PO₄(aq) ⇄ Ca₃(PO₄)₂(s) + 6 NH₄Cl(aq)
The ionic equation includes all the ions (species that dissociate in water) and the species that do not dissociate in water.
3 Ca²⁺(aq) + 6 Cl⁻(aq) + 6 NH₄⁺(aq) + 2 PO₄³⁻(aq) ⇄ Ca₃(PO₄)₂(s) + 6 NH₄⁺(aq) + 6 Cl⁻(aq)
The net ionic equation includes only the ions that participate in the reaction and the species that do not dissociate in water. In does not include <em>spectator ions</em>.
3 Ca²⁺(aq) + 2 PO₄³⁻(aq) ⇄ Ca₃(PO₄)₂(s)
Equilibrium expression is ![Keq = \frac{[H3O+][HCO3^-]}{[H2CO3]}\\](https://tex.z-dn.net/?f=Keq%20%3D%20%5Cfrac%7B%5BH3O%2B%5D%5BHCO3%5E-%5D%7D%7B%5BH2CO3%5D%7D%5C%5C)
<u>Explanation:</u>
Equilibrium expression is denoted by Keq.
Keq is the equilibrium constant that is defined as the ratio of concentration of products to the concentration of reactants each raised to the power its stoichiometric coefficients.
Example -
aA + bB = cC + dD
So, Keq = conc of product/ conc of reactant
![Keq = \frac{[C]^c [D]^d}{[A]^a [B]^b}](https://tex.z-dn.net/?f=Keq%20%3D%20%5Cfrac%7B%5BC%5D%5Ec%20%5BD%5D%5Ed%7D%7B%5BA%5D%5Ea%20%5BB%5D%5Eb%7D)
So from the equation, H₂CO₃+H₂O = H₃O+HCO₃⁻¹
![Keq = \frac{[H3O^+]^1 [HCO3^-]^1}{[H2CO3]^1 [H2O]^1}](https://tex.z-dn.net/?f=Keq%20%3D%20%5Cfrac%7B%5BH3O%5E%2B%5D%5E1%20%5BHCO3%5E-%5D%5E1%7D%7B%5BH2CO3%5D%5E1%20%5BH2O%5D%5E1%7D)
The concentration of pure solid and liquid is considered as 1. Therefore, concentration of H2O is 1.
Thus,
![Keq = \frac{[H3O+][HCO3^-]}{[H2CO3]}\\](https://tex.z-dn.net/?f=Keq%20%3D%20%5Cfrac%7B%5BH3O%2B%5D%5BHCO3%5E-%5D%7D%7B%5BH2CO3%5D%7D%5C%5C)
Therefore, Equilibrium expression is ![Keq = \frac{[H3O+][HCO3^-]}{[H2CO3]}\\](https://tex.z-dn.net/?f=Keq%20%3D%20%5Cfrac%7B%5BH3O%2B%5D%5BHCO3%5E-%5D%7D%7B%5BH2CO3%5D%7D%5C%5C)
Answer: water
Explanation:if you look at a globe most of it is blue and blue on a globe is water so that means water covers most of the earth
MA= output force/ input force
MA= 100N/20N
MA= 50