Answer:
Since with LiBr no precipitation takes place. So, Ag+ is absent
When we add Li2SO4 to it, precipitation takes place.
Ca2+(aq) + SO42-(aq) ----> CaSO4(s) ...Precipitate
Thus, Ca2+ is present.
When Li3PO4 is added, again precipitation takes place.Reaction is:
Co2+(aq) + PO43-(aq)---->Co3(PO4)2(s) ... Precipitate
A. Ca2+ and Co2+ are present in solution
B. Ca2+(aq) + SO42-(aq) ----> CaSO4(s)
C. 3Co2+(aq) + 2PO43-(aq)---->Co3(PO4)2(s)
Answer: D. An increase in entropy
Explanation:
Entropy is the measure of randomness or disorder of a system. If a system moves from an disordered arrangement to an ordered arrangement, the entropy is said to increase and vice versa.
For a reaction to be spontaneous, the enthalpy of the solution must decrease and the entropy must increase.
To overcome a positive enthalpy of solution and allow a solid solute to dissolve in water, an increase in entropy would make the reaction spontaneous as the system would move to a more disordered state.
1st one is E
2nd one is also E
<span>• Benzene has the formula of C6H<span>6 </span>whereas cyclohexane has the formula of C6H<span>12.
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Benzene is an aromatic compound but cyclohexane is not aromatic.
Benzene is an unsaturated molecule, but cyclohexane is saturated.
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Carbon atoms in the benzene ring have sp2 hybridization where carbon atoms in the cyclohexane have sp3 hybridization.</span>
Benzene has a planar structure whereas cyclohexane has chair conformations.<span>
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