Answer:
The α‑helix is held together by hydrogen bonds between the amide N−H and C=O groups.
Disulfide bonds stabilize secondary structure.
Explanation:
Proteins have primary, secondary, tertiary and quartinary structures.
The secondary structure of a protein is the regular, recurring sequence of amino acid in a polypeptide chain. Secondary structure of proteins give rise to the folding observed in the structure of a protein.
The major secondary structures of a protein are α-helices and β-structures.
Answer:
The [H⁺] for this soluton is 2*10⁻³ M
Explanation:
pH, short for Hydrogen Potential and pOH, or OH potential, are parameters used to measure the degree of acidity or alkalinity of substances.
The values that compose them vary from 0 to 14 and the pH value can be directly related to that of pOH by means of:
pH + pOH= 14
In this case, pOH=11.30, so
pH + 11.30= 14
Solving:
pH= 14 - 11.30
pH= 2.7
Mathematically the pH is the negative logarithm of the molar concentration of the hydrogen or proton ions (H⁺) or hydronium ions (H₃O):
´pH= - log [H⁺] = -log [H₃O]
Being pH=2.7:
2.7= - log [H⁺]
[H⁺]= 10⁻² ⁷
[H⁺]=1.995*10⁻³ M≅ 2*10⁻³ M
<u><em>The [H⁺] for this soluton is 2*10⁻³ M</em></u>
Answer:
The correct answer is 596.5 kJ.
Explanation:
The mass of ethanol or C2H5OH mentioned in the question is 20 gm.
The molar mass of ethanol is 46 g/mol.
The moles of the compound can be determined by using the formula,
n = weight of the compound/molar mass
= 20/46 = 0.435 moles
It is mentioned in the question that standard heat of combustion of ethanol is 1372 kJ/mole, that is, one mole of ethanol is producing 1372 kilojoules of energy at the time of combustion.
Therefore, the energy liberated by completely burning the 20 grams of ethanol is 0.435*1372 = 596.5 kJ.
<span>A. biosphere
</span><span>C. geosphere
</span>E. atmosphere
<span>F. hydrosphere
</span>
Earth's oceans absorb carbon dioxide emitted by humans and other animals, and eventually turn it into carbonate rocks. Which "spheres" are part of this<span>process? Select all that apply.
</span>
NOT:
<span>B. exosphere
</span><span>D. cryosphere</span>
