Its to protect the cell from its surroundings, its selectively permeable to ions and organic molecules
First convert to moles:
0.5113 g / 17 g/mol = 0.0301 mol
Now create a ratio based on the reaction provided to solve for the unknown:
4 NH3 / -905.4 kJ = 0.0301 mol NH3 / x kJ
x = -6.808 kJ
25.9 kJ/mol. (3 sig. fig. as in the heat capacity.)
<h3>Explanation</h3>
The process:
.
How many moles of this process?
Relative atomic mass from a modern periodic table:
- K: 39.098;
- N: 14.007;
- O: 15.999.
Molar mass of
:
.
Number of moles of the process = Number of moles of
dissolved:
.
What's the enthalpy change of this process?
for
. By convention, the enthalpy change
measures the energy change for each mole of a process.
.
The heat capacity is the least accurate number in these calculation. It comes with three significant figures. As a result, round the final result to three significant figures. However, make sure you keep at least one additional figure to minimize the risk of rounding errors during the calculation.
The answer is False. The formation of the moon did not cause the Paleozoic extinction. The moon formed during the Precambrian era.