Name:<span> Polonium </span>
Symbol:<span> Po </span>
Atomic Number:<span> 84 </span>
Atomic Mass:<span> (209.0) amu </span>
Melting Point:<span> 254.0 °C (527.15 K, 489.2 °F) </span>
Boiling Point:<span> 962.0 °C (1235.15 K, 1763.6 °F) </span>
Number of Protons/Electrons:<span> 84 </span>
Number of Neutrons:<span> 125 </span>
Classification: Metalloid
Crystal Structure:<span> Monoclinic </span>
Density @ 293 K:<span> 9.4 g/cm</span>3
Color:<span> Unknown</span>
Atomic Structure<span> <span>
Number of Energy Levels: 6<span>
First Energy Level: 2
Second Energy Level: 8
Third Energy Level: 18
Fourth Energy Level: 32
Fifth Energy Level: 18
Sixth Energy Level: 6
does it help?</span></span></span>
Answer:
(a) Ala; (b) Tyr; (c) Ser; (d) His
Explanation:
The general formula for an amino acid is NH₂-CH(R)-COOH
The differences among the different amino acids is caused by the side groups R.
(a) Ala, Leu
Ala: R = CH₃-
Leu: R = (CH₃)₂CHCH₂-
Leucine has a larger hydrophobic side group. It should be the less soluble of the pair,
Alanine is the more soluble amino acid.
(b) Tyr, Phe
Tyr: R = HOC₆H₄CH₂-
Phe: R = C₆H₅CH₂-
Tyrosine has a polar OH group. It can form hydrogen bonds with water.
Tyrosine is the more soluble amino acid.
(c) Ser, Ala
Ser: R = HOCH₂-
Ala: R = CH₃-
Serine has a polar OH group. It can form hydrogen bonds with water.
Serine is the more soluble amino acid.
(d) Trp, His
Trp: R = Indole-CH₂-
His: R = Imidazole-CH₂-
Tryptophan has a large aromatic hydrophobic side chain.
Histidine is a basic amino acid. At pH 7 it exists mainly as the anion NH₂CHRCOO⁻, which is hydrophilic.
Histidine is the more soluble amino acid.
C. Hydropower would need dams to be built, and this will prevent fishes from going upstream.
Answer:
C
Explanation:
It is letter C since you are currently experimenting to see if by the amount of rainfall it gets it can <em><u>grow</u></em><em><u> </u></em><em><u>more</u></em><em><u> </u></em><em><u>or</u></em><em><u> </u></em><em><u>less</u></em>. So you control the amount of rain