Answer:
Molar heat of solution of KBr is 20.0kJ/mol
Explanation:
Molar heat of solution is defined as the energy released (negative) or absorbed (Positive) per mole of solute being dissolved in solvent.
The dissolution of KBr is:
KBr → K⁺ + Br⁻
In the calorimeter, the temperature decreases 0.370K, that means the solution absorbes energy in this process. The energy is:
q = 1.36kJK⁻¹ × 0.370K
q = 0.5032kJ
Moles of KBr in 3.00g are:
3.00g × (1mol / 119g) = 0.0252moles
Thus, molar heat of solution of KBr is:
0.5032kJ / 0.0252moles = <em>20.0kJ/mol</em>
0.01 cubic meters
Hope this helps
Answer:
D. Surface tension.
Explanation:
Surface tension is defined as the energy required to increase the surface area of a liquid by a unit amount.
The surface tension of a liquid results from an imbalance of intermolecular attractive forces, the cohesive forces between molecules:
A molecule in a liquid experiences cohesive forces with other molecules in all directions while molecules at the surface of a liquid experiences only net inward cohesive forces.
Answer:
a H2CO3 b HCO3- and c H+ and HCO3-
Explanation:
As the pKa value of phenol is more than that of carbonic acid(H2CO3), the carbonic acid will have high Ka value than that of phenol.
The acid that contain high Ka value act as stong acid.From that point of view H2CO3 is a strong acid than phenol as the Ka value of carbonic acid is greater than that of phenol.
The conjugate base of H2CO3 is bicarbonate ion(HCO3-)
c The species that predorminates at equilibrium are H+ and HCO3-
The only metal that is a liquid at room temperature is mercury!!
