Answer:
did you you know
Explanation: thcco lot iof the
The ML of 0.85 m NaOH required to titrate 25 ml of 0.72m hbr to the equivalence point is calculated as follows
calculate the moles of HBr used
moles = molarity x volume
25 x0.072/1000= 0.0018 moles
write the equation for reaction
NaOH + HBr = NaBr + H2O
from reacting equation the mole ratio between NaOH to HBr is 1:1 therefore the moles of NaOH = 0.0018 moles
volume = moles/molarity
0.0018/0.085 = 0.021 L in Ml = 0.021 x1000=21.18 Ml ofNaOH
Answer:
25.2 kJ
Explanation:
The complete question is presented in the attached image to this answer.
Note that, the heat gained by the 2.00 L of water to raise its temperature from the initial value to its final value comes entirely from the combustion of the benzoic acid since there are no heat losses to the containing vessel or to the environment.
So, to obtained the heat released from the combustion of benzoic acid, we just calculate the heat required to raise the temperature of the water.
Q = mCΔT
To calculate the mass of water,
Density = (mass)/(volume)
Mass = Density × volume
Density = 1 g/mL
Volume = 2.00 L = 2000 mL
Mass = 1 × 2000 = 2000 g
C = specific heat capacity of water = 4.2 J/g.°C
ΔT = (final temperature) - (Initial temperature)
From the graph,
Final temperature of water = 25°C
Initial temperature of water = 22°C
ΔT = 25 - 22 = 3°C
Q = (2000×4.2×3) = 25,200 J = 25.2 kJ
Hope this Helps!!!
Answer:
The density of Lithium β is 0.5798 g/cm³
Explanation:
For a face centered cubic (FCC) structure, there are total number of 4 atoms in the unit cell.
we need to calculate the mass of these atoms because density is mass per unit volume.
Atomic mass of Lithium is 6.94 g/mol
Then we calculate the mass of four atoms;

⇒next, we estimate the volume of the unit cell in cubic centimeter
given the edge length or lattice constant a = 0.43nm
a = 0.43nm = 0.43 X 10⁻⁹ m = 0.43 X 10⁻⁹ X 10² cm = 4.3 X 10⁻⁸cm
Volume of the unit cell = a³ = (4.3 X 10⁻⁸cm)³ = 7.9507 X 10⁻²³ cm³
⇒Finally, we calculate the density of Lithium β
Density = mass/volume
Density = (4.6097 X 10⁻²³ g)/(7.9507 X 10⁻²³ cm³)
Density = 0.5798 g/cm³