Flammability is a chemical change because when you burn something, it no longer has the same properties.
Answer:
The vapor pressure of the solution is 23.636 torr
Explanation:

Where;
is the vapor pressure of the solution
is the mole fraction of the solvent
is the vapor pressure of the pure solvent
Thus,
15.27 g of NaCl = [(15.27)/(58.5)]moles = 0.261 moles of NaCl
0.67 kg of water = [(0.67*1000)/(18)]moles = 37.222 moles of H₂O
Mole fraction of solvent (water) = (number of moles of water)/(total number of moles present in solution)
Mole fraction of solvent (water) = (37.222)/(37.222+0.261)
Mole fraction of solvent (water) = 0.993
<u>Note:</u> the vapor pressure of water at 25°C is 0.0313 atm
Therefore, the vapor pressure of the solution = 0.993 * 0.0313 atm
the vapor pressure of the solution = 0.0311 atm = 23.636 torr
The molecular structure of the solids has lower ability to conduct electricity due to tight holding by nucleus.
<h3>Why molecular solids are poor conductors?</h3>
Molecular solids are also poor conductors of electricity because their valence electrons are tightly held by the nuclear charges present in the nucleus while on the other hand, Metals are good electrical conductors in the solid form due to the presence of free electrons that helps in the conduction of electricity.
Learn more about electricity here: brainly.com/question/25144822
I don’t understand. Is there a picture? Where are the options?
Answer:
The ΔH is 5.5 kJ/mol and the reaction is endothermic.
Explanation:
To calculate the ∆H (heat of reaction) of the combustion reaction, that is, the heat that accompanies the entire reaction, you must make the total sum of all the heats of the products and of the reagents affected by their stoichiometric coefficient ( number of molecules of each compound participating in the reaction) and finally subtract them:
Combustion enthalpy = ΔH = ∑H products - ∑Hreactants
In this case:
ΔH = 15.7 kJ/mol - 10.2 kJ/mol= 5.5 kJ/mol
An endothermic reaction is one whose enthalpy value is positive, that is, the system absorbs heat from the environment (ΔH> 0).
<u><em>The ΔH is 5.5 kJ/mol and the reaction is endothermic.</em></u>