All categories

2 years ago

Select the true statements about protein secondary structure.

Chemistry

1 answer:

netineya [11]2 years ago

7 0

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.

You might be interested in

The increase in the rate of solvation with a rise in solvent temperature is mainly due to a(n)

katrin2010 [14]

The answer would be b

3 0

2 years ago

one kilogram of water (V1 = 1003 cm^3*kg-1) in a piston cylinder device at (25°C) and 1 bar is compressed in a mechanically reve

vova2212 [387]

Answer:

Q = -18118.5KJ

W = -18118.5KJ

∆U = 0

∆H = 0

∆S = -60.80KJ/KgK

Explanation:

W = RTln(P1/P2)

P1 = 1bar = 100KN/m^2, P2 = 1500bar = 1500×100 = 150000KN/m^2, T = 23°C = 23 + 273K = 298K

W = 8.314×298ln(100/150000) = 8.314×298×-7.313 = -18118.5KJ ( work is negative because the isothermal process involves compression)

∆U = Cv(T2 - T1)

For an isothermal process, temperature is constant, so T2 = T1

∆U = Cv(T1 - T1) = Cv × 0 = 0

Q = ∆U + W = 0 + (-18118.5) = 0 - 18118.5 = -18118.5KJ

∆H = Cp(T2 - T1)

T2 = T1

∆H = Cp(T1 - T1) = Cp × 0 = 0

∆S = Q/T

Mass of water = 1kg

Heat transferred (Q) per kilogram of water = -18118.5KJ/Kg

∆S = (-18118.5KJ/Kg)/298K = -60.80KJ/KgK

4 0

2 years ago

Describe a way to separate a mixture of sand and salt .

worty [1.4K]

Put water in it and the salt will dissolve and the sand will stay at the bottom

7 0

2 years ago

For the following reactions, write a balanced equation using half-reactions and calculate the voltage to be expected.

Iteru [2.4K]

a) $2Na(s) +2H_2O(I)$ → $2Na^+(aq) + OH^-(aq)+ H_2(g)$

b) $2Ag (s) +2H^(aq)$ → $2 Ag^+ (aq) +H_2(g)$

<h3>What are half-reactions?</h3>

The half-reaction method is a way to balance redox reactions. It involves breaking the overall equation down into an oxidation part and a reduction part.

$2Na(s) +2H_2O(I)$ → $2Na^+(aq) + OH^-(aq)+ H_2(g)$

$E^0 cell = E^0 (reduction) - E^0 (oxidation)$