The pH of the solution affects the ionization of the R group of the amino acids in the enzyme. Changes in ionization affects the bonding of the protein. Consequently, affects the shape. Therefore, the substrate binding to the site will lessen causing a reduce enzyme activity. But this depends on the type of enzyme and its optimum pH level.
A radioactive half-life talks about the amount of time
it takes for half of the original isotope to deteriorate.
The solution for this problem is:
Half-life (lst order
reaction) = ln2 over k <span>
<span>so half-life = .693 over 3.25 = .213 day is the
half-life for the metabolism reaction</span></span>
<span> </span>
Given parameters;
Mass of gold colored metal beads = 425g
Volume of water displaced by beads = 48.0cm³
Unknown;
Identity of the metal = ?
Given densities;
Gold: 19.3 g/mL
Copper: 8.86 g/mL
Bronze: 9.87 g/mL
Density is an intensive property of any substance. This implies that we can use the density of any substance to identify it.
Density can be defined as the mass per unit volume of a substance. Every substance has a unique mass per volume.
Mathematically;
Density =
where mass is in kg or g
volume is in m³ or cm³
To find the density, we must know the mass and volume.
In this problem, the volume of the gold metal beads is the same as the volume of water displaced. This is a way to measure volume of solids.
Since the volume is given in cm³, and we are comparing with choices that have units in g/mL, we simply convert the volume in cm³ to mL
1cm³ = 1mL³
So therefore, volume of gold colored metal is 48mL
Now input the parameters given and solve for the density;
Density = = 8.85g/mL
From the given densities, we clearly see that copper is the metal since they both of similar densities.
PubChem CID: 142982
Chemical Names: 4-Ethyl-2,2-dimethylhexane; Hexane, 4-ethyl-2,2-dimethyl-; 52896-99-8; 2,2-dimethyl-4-ethylhexane; AC1L3M80; Hexane,4-ethyl-2,2-dimethyl- More...
Molecular Formula: C10H22
Molecular Weight: 142.286 g/mol
InChI Key: QHLDBFLIDFTHQI-UHFFFAOYSA-N
Freezing point depression, ΔT, is calculated using the
formula:
ΔT= - Kf * molal
Where molal is the molality of the solute (moles solute/kg solvent)
In this case the solute is Barium Chloride while the solvent
is Water. The formula for molality is:
molal = (mass of solute / molar mass solute) / (mass of solvent)
molal = (116.8 g / 208.23 g/mol) / (0.25 kg Water) =
molal= 2.24 mol/kg = 2.24 m
Substituting to the 1st equation:
ΔT= - 1.86 °C/m
(2.24 m)
ΔT=
-4.17 °C
So the answer is A.