Answer:
Explanation:
Hello,
Considering the chemical reaction, the enthalpy of reaction is given by:
ΔH°rxn=ΔfHCO2+ΔfHH2O-ΔfHC8H18
(ΔfHO2=0)
Taking into account that the reaction produces energy, ΔH°rxn is negative. No, solving for ΔfHC8H18:
ΔfHC8H18=-ΔH°rxn+8*ΔfHCO2+9*ΔfHH2O
ΔfHC8H18=-(-5104.1 kJ/mol)+9*(-292.74kJ/mol)+8*(-393.5 kJ/mol)
ΔfHC8H18=-678.56 kJ/mol
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<span>Physical change, heat caused this.
Water molecules that only vibrate are in solid form. If heat energy is added, the molecules will speed up their vibrations until they can break loose from the organized pattern of a solid and begin to slide over each other, changing to liquid state. If more heat energy is added, the molecules will speed up more and move randomly in all directions as a gas/vapor. Removing heat energy will reverse these changes.
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Answer:
The system shifts forward
Explanation:
The forward reaction is favoured in order to reduce the disruption (excess heat) to the system. Position of equilibrium shifts rightwards of the equation for excess heat to be absorbed during the endothermic forward reaction
Answer : (4) Chromatography
Explanation :
Chromatography : It is a separation technique of a mixture by passing it through a medium in which components travels at different rates.
There are many types of chromatography but this is paper chromatography.
Paper chromatography : It is used to separate the colored substances. In paper chromatography, water is the mobile phase and paper is the stationary phase. The mixture of components moves at different speeds through the stationary phase so that they can be separated.
In paper chromatography, several colors can be separated based on their solubility. The more soluble a color is, the more readily it will dissolve in mobile phase and farther it will travel.