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.
Answer:
The cube A is magnesium, the cube B is aluminum and the cube C is silver.
Explanation:
Density is defined by the expression 
where m is the mass and V is the volume, therefore:
- Density of the cube A:
- Density of the cube B:
- Density of the cube C:
Solving for mass:
And all the three cubes have the same mass, so:
Therefore:
(Eq.1)
(Eq.2)
Solving for 
in Eq.1:
Replacing values for the volume:
As we know the density of the aluminum is 
, so replacing this value for 
:
that is the density of the magnesium.
Solving for 
in Eq.2:
That is the density of the silver.
Therefore the cube A is magnesium, the cube B is aluminum and the cube C is silver.
Answer:
Chargaff's rule, also known as the complementary base pairing rule, states that DNA base pairs are always adenine with thymine (A-T) and cytosine with guanine (C-G). A purine always pairs with a pyrimidine and vice versa. However, A doesn't pair with C, despite that being a purine and a pyrimidine.
Explanation:
In these nucleotides, there is one of the four possible bases: adenine (A), guanine (G), cytosine (C), or thymine (T) (Figure below). Adenine and guanine are purine bases, and cytosine and thymine are pyrimidine bases. Chemical structure of the four nitrogenous bases in DNA✔✔
Answer:
5.22 atm
Explanation:
The following data were obtained from the question:
Number of mole (n) = 2 moles
Volume (V) = 10 L
Temperature (T) = 45 °C
Pressure (P) =?
Next, we shall convert 45 °C to Kelvin temperature. This can be obtained as follow:
Temperature (K) = Temperature (°C) + 273
T (K) = T (°C) + 273
T (°C) = 45 °C
T(K) = 45 °C + 273
T (K) = 318 K
Finally, we shall determine the pressure of the gas by using the ideal gas equation as shown below:
Number of mole (n) = 2 moles
Volume (V) = 10 L
Temperature (T) = 318 K
Gas constant (R) = 0.0821 atm.L/Kmol
Pressure (P) =.?
PV = nRT
P x 10 = 2 x 0.0821 x 318
Divide both side by 10
P = (2 x 0.0821 x 318) /10
P = 5.22 atm
Therefore, the pressure of the gas is 5.22 atm
Answer:
Remain unchanged.
Explanation:
The total number of moles of liquid remain unchanged as the some moles of species B are added to the system because specie B that is added in the liquid phase is again restored after addition. If the specie B did not restored after addition to the liquid phase so the total number of moles increases in the liquid phase so that's why we can say that the liquid phase remain unchanged.
