Answer : The final temperature of the solution in the calorimeter is, 
Explanation :
First we have to calculate the heat produced.
where,
= enthalpy change = -44.5 kJ/mol
q = heat released = ?
m = mass of 
= 1.52 g
Molar mass of = 40 g/mol
Now put all the given values in the above formula, we get:
Now we have to calculate the final temperature of solution in the calorimeter.
where,
q = heat produced = 1.691 kJ = 1691 J
m = mass of solution = 1.52 + 35.5 = 37.02 g
c = specific heat capacity of water = 
= initial temperature = 
= final temperature = ?
Now put all the given values in the above formula, we get:
Thus, the final temperature of the solution in the calorimeter is,
This problem handles<em> boiling-point elevation</em>, which means we will use the formula:
ΔT = Kb * m
Where ΔT is the difference of Temperature between boiling points of the solution and the pure solvent (Tsolution - Tsolvent). Kb is the ebullioscopic constant of the solvent (2.64 for benzene), and m is the molality of the solution.
Knowing that benzene's boiling point is 80.1°C, we <u>solve for m</u>:
Tsolution - Tsolvent = Kb * m
80.23 - 80.1 = 2.64 * m
m = 0.049 m
We use the definition of molality to <u>calculate the moles of azulene</u>:
0.049 m = Xmoles azulene / 0.099 kgBenzene
Xmoles azulene = 4.87 x10⁻³ moles azulene
We use the mass and the moles of azulene to<u> calculate its molecular weight</u>:
0.640 g / 4.875 x10⁻³ mol = 130.28 g/mol
<em>A molecular formula that would fulfill that molecular weight</em> is C₁₀H₁₀. So that's the result of solving this problem.
The actual molecular formula of azulene is C₁₀H₈.
Answer:
indicator
Explanation:
Indicators are the weak organic dyes which shows different colors in acidic and basic mediums.
Due to the fact that a noticeable pH change occurs near the equivalence point of acid-base titrations, an indicator can be used to signal the end point of a titration.
Therefore, choosing the proper indicator, scientists can minimize the difference in these two numbers, allowing more accurate measurements in the lab.
Answer:
2.0000 g
Explanation:
It will show the number out to the 4th decimal place. Exactly 2 g will be displayed as 2.0000 g.
