When it comes to physical changes like phase changes, there are two types of heat energy: sensible heat and latent heat. Sensible heat is the heat absorbed/released when you heat the substance but it doesn't change phase. An example would be heating lukewarm water. The substance is liquid all throughout. Latent heat, on the other hand, is the heat absorbed/released when there is a phase change. An example would be boiling water, because it changes liquid to vapor.
Hence, for freezing liquid, you use the latent heat, specifically the heat of fusion. The answer should be
2.5 g * (1 mol/18.02 g) * 6.03 kJ/mol = 0.84 kJ/mol
The answer is not in the choices. You only use Hvap if you boil water.
Part 1)
Cu- <span>[Ar] 3d¹⁰4s¹ </span><span>atomic number: 29
</span>
<span>O- [He] 2s2 2p<span>4 atomic number:8
</span></span>La- <span>[Xe] 5d¹ 6s² </span><span>atomic number:57
Y- </span><span>[Kr] 4d¹5s² </span><span>atomic number:39
Ba- </span><span>[Xe] 6s² </span><span>atomic number:56
Tl- </span><span>[Xe] 4f¹⁴ 5d¹⁰ 6s² 6p¹ </span><span>atomic number:81
Bi- </span> <span>[Xe] 4f¹⁴ 5d¹⁰ 6s² 6p³ </span>atomic number:83
Part 2)
You are able to this by consulting the periodic table and following this steps:
-Find your atom's atomic number;
<span>-Determine the charge of the atom (these were all uncharged)
</span><span>-Memorize the order of orbitals (s, d, p, d.. and how many electrons they can fit)
</span>-<span>Fill in the orbitals according to the number of electrons in the atom
- </span><span>for long electron configurations, abbreviate with the noble gases</span>
Well depends on what type of fish the parent is but i guess you can say:
what they eat
teeth
instincts
color
venom
blending in,etc