Interpretation:
Whether the concentration of nitrates in water can be decreased by boiling, or not, is to be explained.
Concept Introduction:
Water gets polluted due to the presence of various biological and chemical contaminants in it. Biological contaminants include microorganisms such as Giardia, Legionella while chemical contaminants are mercury, lead, benzene, trichloroethylene etc. Both these render water unfit for consumption by human beings and animals, if the contaminant exceeds a certain limit, termed as Maximum Contaminant Limit.
The concentration of a contaminant is reported as the mass of contaminant (in milligrams) present in one liter of water.
Hard water is a solution of calcium and magnesium salts in water. Presence of calcium and magnesium ions makes water hard and renders it unusable for various purposes, such as cleaning clothes and utensils, bathing and in water heaters etc.
Boiling of water cannot get rid of contaminants because this decreases the total volume of the sample but the mass of the contaminant remains same. Moreover, the concentration of the contaminant increases.
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CHEMISTRY IN FOCUS W/ OWL (LL)>IP<
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- need help please and thanks dont understand only need help with C-F Learning Goal: As discussed during the lecture, the enzyme HIV-1 reverse transcriptae (HIV-RT) plays a significant role for the HIV virus and is an important drug target. Assume a concentration [E] of 2.00 µM (i.e. 2.00 x 10-6 mol/l) for HIV-RT. Two potential drug molecules, D1 and D2, were identified, which form stable complexes with the HIV-RT. The dissociation constant of the complex ED1 formed by HIV-RT and the drug D1 is 1.00 nM (i.e. 1.00 x 10-9). The dissociation constant of the complex ED2 formed by HIV-RT and the drug D2 is 100 nM (i.e. 1.00 x 10-7). Part A - Difference in binding free eenergies Compute the difference in binding free energy (at a physiological temperature T=310 K) for the complexes. Provide the difference as a positive numerical expression with three significant figures in kJ/mol. The margin of error is 2%. Part B - Compare difference in free energy to the thermal…arrow_forwardneed help please and thanks dont understand only need help with C-F Learning Goal: As discussed during the lecture, the enzyme HIV-1 reverse transcriptae (HIV-RT) plays a significant role for the HIV virus and is an important drug target. Assume a concentration [E] of 2.00 µM (i.e. 2.00 x 10-6 mol/l) for HIV-RT. Two potential drug molecules, D1 and D2, were identified, which form stable complexes with the HIV-RT. The dissociation constant of the complex ED1 formed by HIV-RT and the drug D1 is 1.00 nM (i.e. 1.00 x 10-9). The dissociation constant of the complex ED2 formed by HIV-RT and the drug D2 is 100 nM (i.e. 1.00 x 10-7). Part A - Difference in binding free eenergies Compute the difference in binding free energy (at a physiological temperature T=310 K) for the complexes. Provide the difference as a positive numerical expression with three significant figures in kJ/mol. The margin of error is 2%. Part B - Compare difference in free energy to the thermal…arrow_forwardPlease correct answer and don't used hand raitingarrow_forward
- need help please and thanks dont understand a-b Learning Goal: As discussed during the lecture, the enzyme HIV-1 reverse transcriptae (HIV-RT) plays a significant role for the HIV virus and is an important drug target. Assume a concentration [E] of 2.00 µM (i.e. 2.00 x 10-6 mol/l) for HIV-RT. Two potential drug molecules, D1 and D2, were identified, which form stable complexes with the HIV-RT. The dissociation constant of the complex ED1 formed by HIV-RT and the drug D1 is 1.00 nM (i.e. 1.00 x 10-9). The dissociation constant of the complex ED2 formed by HIV-RT and the drug D2 is 100 nM (i.e. 1.00 x 10-7). Part A - Difference in binding free eenergies Compute the difference in binding free energy (at a physiological temperature T=310 K) for the complexes. Provide the difference as a positive numerical expression with three significant figures in kJ/mol. The margin of error is 2%. Part B - Compare difference in free energy to the thermal energy Divide the…arrow_forwardPlease correct answer and don't used hand raitingarrow_forwardPlease correct answer and don't used hand raitingarrow_forward
- Can you tell me if my answers are correctarrow_forwardBunsenite (NiO) crystallizes like common salt (NaCl), with a lattice parameter a = 4.177 Å. A sample of this mineral that has Schottky defects that are not supposed to decrease the volume of the material has a density of 6.67 g/cm3. What percentage of NiO molecules is missing? (Data: atomic weight of Ni: 58.7; atomic weight of O: 16).arrow_forwardA sample of aluminum (face-centered cubic - FCC) has a density of 2.695 mg/m3 and a lattice parameter of 4.04958 Å. Calculate the fraction of vacancies in the structure. (Atomic weight of aluminum: 26.981).arrow_forward
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