Answer:
The product is significantly impure
Explanation:
In order to test for the purity of a specific sample that was synthesized, the melting point of a compound is measured. Basically speaking, the melting point identifies how pure a compound is. There are several cases that are worth noting:
- if the measured melting point is significantly lower than theoretical, e. g., lower by 3 or more degrees, we conclude that our compound contains a substantial amount of impurities;
- wide range in the melting point indicates impurities, unless it agrees with the theoretical range.
Since our compound is even 10 degrees Celsius lower than expected, it indicates that the compound is significantly impure.
Answer:
The heat of combustion is -25 kJ/g = -2700 kJ/mol.
Explanation:
According to the Law of conservation of energy, the sum of the heat released by the combustion reaction and the heat absorbed by the bomb calorimeter is equal to zero.
Qcomb + Qcal = 0
Qcomb = - Qcal
The heat absorbed by the calorimeter can be calculated with the following expression.
Qcal = C × ΔT
where,
C is the heat capacity of the calorimeter
ΔT is the change in temperature
Then,
Qcomb = - Qcal
Qcomb = - C × ΔT
Qcomb = - 1.56 kJ/°C × 3.2°C = -5.0 kJ
Since this is the heat released when 0.1964 g o quinone burns, the energy of combustion per gram is:
The molar mass of quinone (C₆H₄O₂) is 108 g/mol. Then, the energy of combustion per mole is:
Answer:
See explaination
Explanation:
The Cys3-cys97 and cys21-cys142 disulfides restrict the unfolded state of lysozyme enzyme to a class of more compact structures with a less exposed hydrophobic surface, compared to the unfolded states of reduced/non-crosslinked lysozyme. there are 2 major factors which lead to the stabilization of lysozyme due to disulfide bonds-
1- increase in the loop size due to the formation of disulfide bonds that leads to an increase in the even entropic effect.
2- the region formed should be flexible. the strain energy due to the formation of the disulfide bond is lower.
cys21-cys142 has a higher Tm than the cys3-cys97 because it involves flexible parts of the molecule. 21 and 142 residues are located on opposite sides of the active-site cleft where significant hinge-bending motion is seen. this introduces minimal strain in the protein.
The model<span> of the </span>atom<span> has dramatically </span>changed<span> over many many years.We learn </span>atoms<span> make up different substances and are the smallest particles of matter. which can have subatomic particles that are very small portions of matter.at first scientist only thought there were electrons which are negatively charged.</span>
Answer 19.9g. I’ve took the test last week at my uncle randy’s house
