Answer: northern hemisphere
Explanation: I looked it up. Plus I took a test with this question and when the teacher went over the answer i got it right.
<u>Given:</u>
Change in internal energy = ΔU = -5084.1 kJ
Change in enthalpy = ΔH = -5074.3 kJ
<u>To determine:</u>
The work done, W
<u>Explanation:</u>
Based on the first law of thermodynamics,
ΔH = ΔU + PΔV
the work done by a gas is given as:
W = -PΔV
Therefore:
ΔH = ΔU - W
W = ΔU-ΔH = -5084.1 -(-5074.3) = -9.8 kJ
Ans: Work done is -9.8 kJ
Answer:
Therefore, The indicator that is best fit for the given titration is Bromocresol Green Color change from pH between 4.0 to 5.6
Bromocresol green, color change from pH = 4.0 to 5.6
Explanation:
The equation for the reaction is :
![C_2H_5NH_2_(_a_q_) + H^+_(_a_q_) --- C_2H_5NH_{3(aq)}^+](https://tex.z-dn.net/?f=C_2H_5NH_2_%28_a_q_%29%20%20%20%20%20%2B%20%20%20%20%20H%5E%2B_%28_a_q_%29%20%20%20---%20%20%20%20%20%20C_2H_5NH_%7B3%28aq%29%7D%5E%2B)
concentration of
= 10%
10 g of
in 100 ml solution
molar mass = 45.08 g/mol
number of moles = 10 / 45.08
= 0.222 mol
Molarity of ![C_2H_5NH_2(aq) = 0.222 \times \frac{1000}{100}mL](https://tex.z-dn.net/?f=C_2H_5NH_2%28aq%29%20%3D%200.222%20%5Ctimes%20%5Cfrac%7B1000%7D%7B100%7DmL)
= 2.22 M
number of moles of
in 20 mL can be determined as:
![= 20 mL \times 2.22 M= 44*10^{-3} mole](https://tex.z-dn.net/?f=%3D%2020%20mL%20%5Ctimes%20%202.22%20M%3D%2044%2A10%5E%7B-3%7D%20mole)
Concentration of ![C_2H_5NH_2(aq) = \frac{44*10^{-3}*1000}{20}](https://tex.z-dn.net/?f=C_2H_5NH_2%28aq%29%20%3D%20%5Cfrac%7B44%2A10%5E%7B-3%7D%2A1000%7D%7B20%7D)
= 2.22 M
Similarly, The pKa Value of
is given as 10.75
pKb value will be: 14 - pKa
= 14 - 10.75
= 3.25
the pH value at equivalence point is,
![pH= \frac{1}{2}pKa - \frac{1}{2}pKb-\frac{1}{2}log[C]](https://tex.z-dn.net/?f=pH%3D%20%5Cfrac%7B1%7D%7B2%7DpKa%20-%20%5Cfrac%7B1%7D%7B2%7DpKb-%5Cfrac%7B1%7D%7B2%7Dlog%5BC%5D)
![pH = \frac{14}{2}-\frac{3.25}{2}-\frac{1}{2}log [2.22]](https://tex.z-dn.net/?f=pH%20%3D%20%5Cfrac%7B14%7D%7B2%7D-%5Cfrac%7B3.25%7D%7B2%7D-%5Cfrac%7B1%7D%7B2%7Dlog%20%5B2.22%5D)
![pH = 5.21](https://tex.z-dn.net/?f=pH%20%3D%205.21)
Therefore, The indicator that is best fit for the given titration is Bromocresol Green Color change from pH between 4.0 to 5.6
Answer:
[K₂CrO₄] → 8.1×10⁻⁵ M
Explanation:
First of all, you may know that if you dilute, molarity must decrease.
In the first solution we need to calculate the mmoles:
M = mmol/mL
mL . M = mmol
0.0027 mmol/mL . 3mL = 0.0081 mmoles
These mmoles of potassium chromate are in 3 mL but, it stays in 100 mL too.
New molarity is:
0.0081 mmoles / 100mL = 8.1×10⁻⁵ M