Answer:
a. both temperature changes will be the same
Explanation:
When sodium hydroxide (NaOH) is dissolved in water, a determined amount is released to the solution following the equation:
Q = m×C×ΔT
<em>Where Q is the heat released, m is the mass of the solution, C is the specific heat and ΔH is change in temperature.</em>
Specific heat of both solutions is the same (Because the solutions are in fact the same). Specific heat = C.
m is mass of solutions: 102g for experiment 1 and 204g for experiment 2.
And Q is the heat released: If 2g release X heat, 4g release 2X.
Thus, ΔT in the experiments is:
Experiment 1:
X / 102C = ΔT
Experiment 2:
2X / 204C = ΔT
X / 102C = ΔT
That means,
<h3>a. both temperature changes will be the same</h3>
Answer:
C. The reaction can be broken down and performed in steps
Explanation:
Hess's Law of Constant Heat Summation states that irrespective of the number of steps followed in a reaction, the total enthalpy change for the reaction is the sum of all enthalpy changes corresponding to all the steps in the overall reaction. The implication of this law is that the change of enthalpy in a chemical reaction is independent of the pathway between the initial and final states of the system.
To obtain MgO safely without exposing magnesium to flame, the reaction sequence shown in the image attached may be carried out. Since the enthalpy of the overall reaction is independent of the pathway between the initial and final states of the system, the sum of the enthalpy of each step yields the enthalpy of formation of MgO.
Answer:
Volume of container = 0.0012 m³ or 1.2 L or 1200 ml
Explanation:
Volume of butane = 5.0 ml
density = 0.60 g/ml
Room temperature (T) = 293.15 K
Normal pressure (P) = 1 atm = 101,325 pa
Ideal gas constant (R) = 8.3145 J/mole.K)
volume of container V = ?
Solution
To find out the volume of container we use ideal gas equation
PV = nRT
P = pressure
V = volume
n = number of moles
R = gas constant
T = temperature
First we find out number of moles
<em>As Mass = density × volume</em>
mass of butane = 0.60 g/ml ×5.0 ml
mass of butane = 3 g
now find out number of moles (n)
n = mass / molar mass
n = 3 g / 58.12 g/mol
n = 0.05 mol
Now put all values in ideal gas equation
<em>PV = nRt</em>
<em>V = nRT/P</em>
V = (0.05 mol × 8.3145 J/mol.K × 293.15 K) ÷ 101,325 pa
V = 121.87 ÷ 101,325 pa
V = 0.0012 m³ OR 1.2 L OR 1200 ml
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