Answer: remains constant.
Justification:
1) The phase changes are:
i) Boiling: pass from liquid to gas (absorbs heat energy)
ii) Condensation: pass from gas to liquid (release heat energy)
iii) Melting: pass from solid to liquid (absorb heat energy)
iv) Freezing: pass from liquid to solid (release heat energy)
v) Sublimation: pass from solid to gas (absorbs heat energy)
vii) Deposition: pass from gas to solid (release heat energy)
2) When a phase change occurs, whichever it is, the heat energy related with the process, either absortion or release, is used, to overcome the intermolecular forces (in the case of heat energy absortion) or to create stronger intermolecular forces (in the case of heat energy release).
Because of that, the heat energy exchange does not change the temperature of the substance.
Answer:
28 g solute per 100 g of solution
Explanation:
28% mass means that in all your solution you have 28% of your solute, you could use grames/grames, ml/ml or whatever you want to. So if you are working with a 100 grams solution, 28 grams of that solution must be solute if you want a 28% mass. So, the correct answer is 28 g solute per 100 g of solution.
Answer:
C).
Explanation:
Because the organs in our body helps us to function.
Answer:
2,2,4-trimethylpentane has the higher heat of combustion in kcal/mol.
Explanation:
Heat of combustion is defined as heat evolved on combustion of 1 mole of a substance.
2,2,4-trimethylpentane has the higher heat of combustion in kcal/mol.
Heat combustion of 2,2,4-trimethylpentane = (1304 kcal/mol) and

1 mole of 2,2,4-trimethylpentane on combustion gives 8 mole sof carbon dioxide gas and 9 moles of water.
Heat combustion of ethanol = (327 kcal/mol)

1 mole of ethanol on combustion gives 2 moles of carbon dioxide gas and 3 mole of water.
Heat combustion of ethanol < Heat combustion of 2,2,4-trimethylpentane