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)
The simple machine used is called atwood machine.
To Find :
The volume of 12.1 moles hydrogen at STP.
Solution :
We know at STP, 1 mole of gas any gas occupy a volume of 22.4 L.
Let, volume of 12.1 moles of hydrogen is x.
So, x = 22.4 × 12.1 L
x = 271.04 L
Therefore, the volume of hydrogen gas at STP is 271.04 L.
For the first question, the correct answer among the choices listed is option A, a chocolate bar melting in hot car. It is an endothermic process because it absorbs heat energy for it to be melted. For the second question, it think the correct answer is the last option, <span>(-2222) + (-1182) - (-1144).</span>
