Answer:
Beryllium has an electronic configuration of 1s2 2s2 in its natural state. When in an ion state of Be2+ it loses the electrons in a 2s shell and has a configuration of 1s2. This means that Be2+ has 2 electrons.
The answer is -60.57 = -60.6 KJ.
CaC2(s) + 2 H2O(l) ---> Ca(OH)2(s) +C2H2(g) H= -127.2 KJ
Hf C2H2 = 226.77
Hf Ca(OH)2 = -986.2
<span>Hf H2O = -285.83
Now,
</span><span>add them up. 226.77 - 986.2 + (2*285.83) = -187.77
</span><span>Add back the total enthalpy that is given in the question
-187.77+127.2 = -60.57 </span>
When you add salt to water, you lower to freezing point of the substance.
So for example, normal water freezes at 0°C. But water with salt in it won't freeze at 0°C, because its freezing point is lowered.
In answer to the question. It takes longer for water with salt in it to freeze because the substance requires a lower temperature than normal water to freeze.
it is a <em>Chemical property</em>
Global warming, the gradual increase of the temperature of the earth's lower atmosphere as a result of the increase in greenhouse gases since the Industrial Revolution. Global warming and its effects, such as more intense summer and winter storms, are also referred to as climate change.