A physical property is what a substance is like; it's directly observable. On the other hand, a chemical property is how a substance behaves; its reactivity.
Examples of a physical property are: color, texture, boiling point, freezing point, and melting point.
Examples of a chemical property are: flammability, combustion, and formation of a precipitate.
Explanation:
1. Thermochemical equation is balance stoichiometric chemical equation written with the phases of the reactants and products in the brackets along with the enthalpy change of the reaction.
The given correct thermochemical reactions are:


2. Phase change affect the value of the enthalpy change of the thermochemical equation. This is because change in phase is accompanied by change in energy. For example:


In both reaction phase of water is changing with change in energy of enthalpy of reaction.
Answer: The osmotic pressure of a solution is 53.05 atm
Explanation:
To calculate the concentration of solute, we use the equation for osmotic pressure, which is:

Or,

where,
= osmotic pressure of the solution = ?
i = Van't hoff factor = 1 (for non-electrolytes)
Mass of solute (methanol) = 22.3 g
Volume of solution = 321 mL
R = Gas constant = 
T = temperature of the solution = ![25^oC=[273+25]=298K](https://tex.z-dn.net/?f=25%5EoC%3D%5B273%2B25%5D%3D298K)
Putting values in above equation, we get:


Hence, the osmotic pressure of a solution is 53.05 atm
Answer:
A
Explanation:
Because in 1 second, line A was faster than line B.
The answer should be A. Because the energy in gasoline is called chemical. When burned it is heat, Then to power a vehicle, it is mechanical energy. But I don't know whether the question wants to mean that the energy in the gasoline will not convert totally to the heat, so it will lose. But if think like this, when heat energy transform to mechanical, it will lose again. So I think the answer is A.