Answer:
C. 2.4 M
Explanation:
Because you started with 12M solution of KCl, that means that there was a concentration of 12 mols of KCl per Liter of solution. (12mol/1L =12 M). Since there was only 0.5L of solution, there was only 6 mols of KCl because there is only 12 mols per 1 Liter, so half of that volume would have half the amount of solute to keep that true. (6mol/.5L = 12 M). With the new water added, the formula becomes (6mols KCl/ 2.5L of water =2.4 M)
Im sure that the answer is C, correct me if im wrong.
<span>5.75 moles
The formula for methyl tert-butyl ether is (CH3)3COCH3, so a single molecule has 5 carbon, 12 hydrogen, and 1 oxygen atoms. So for every 12 moles of hydrogen, there's 1 mole of oxygen. So simply divide the number of moles of hydrogen by 12 to get the number of moles of oxygen.
69.0 / 12 = 5.75
Therefore there's 5.75 moles of oxygen in the sample.</span>
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.
