Answer:
333.7 g.
Explanation:
- The depression in freezing point of water (ΔTf) due to adding a solute to it is given by: <em>ΔTf = Kf.m.</em>
Where, ΔTf is the depression in water freezing point (ΔTf = 20.0°C).
Kf is the molal freezing point depression constant of the solvent (Kf = 1.86 °C/m).
m is the molality of the solution.
<em>∴ m = ΔTf/Kf</em> = (20.0°C)/(1.86 °C/m) = <em>10.75 m.</em>
molaity (m) is the no. of moles of solute per kg of the solvent.
∵ m = (no. of moles of antifreeze C₂H₄(OH)₂)/(mass of water (kg))
∴ no. of moles of antifreeze C₂H₄(OH)₂ = (m)(mass of water (kg)) = (10.75 m)(0.5 kg) = 5.376 mol.
∵ no. of moles = mass/molar mass.
<em>∴ mass of antifreeze C₂H₄(OH)₂ = no. of moles x molar mass </em>= (5.376 mol)(62.07 g/mol) =<em> 333.7 g.</em>
Answer:
B) hyperbolic curve; saturated with substrate
Explanation:
Enzymatic kinetics studies the speed of enzyme catalyzed reactions. These studies provide direct information about the mechanism of the catalytic reaction and the specificity of the enzyme. The speed of a reaction catalyzed by an enzyme can be measured with relative ease, since in many cases it is not necessary to purify or isolate the enzyme. The measurement is always carried out under the optimal conditions of pH, temperature, presence of cofactors, etc., and saturating substrate concentrations are used. Under these conditions, the reaction rate observed is the maximum speed (Vmax). The speed can be determined either by measuring the appearance of the products or the disappearance of the reagents.
Following the rate of appearance of product (or disappearance of the substrate) as a function of time, the so-called reaction progress curve is obtained, or simply, the reaction kinetics. This curve is represented by a hyperbolic curve
The k is the proportionality constant of the reaction. Graphically, this is the slope of the graph. Since the graph is linear, then there is only 1 value of k. To calculate this, choose two random points in the line. Suppose we use (0.15,10) and (0.30,20), calculate for the slope.
Slope = k = (10 - 20)/(0.15 - 0.30) = 66.67 mL CO₂/g CaCO₃
The definition of pseudoscience is collection of beliefs or practices mistakenly regarded as being based on scientific method. which B is very similar to that. I believe the answer is A.
Have a nice day.
