Answer:
The concentration of acetic acid is 8.36 M
Explanation:
Step 1: Data given
Volume of acetic acid = 1.00 mL = 0.001 L
Volume of NaOH = 32.40 mL = 0.03240 L
Molarity of NaOH = 0.258 M
Step 2: The balanced equation
CH3COOH + NaOH → CH3COONa + H2O
Step 3: Calculate the concentration of the acetic acid
b*Ca*Va = a*Cb*Vb
⇒with b = the coefficient of NaOH = 1
⇒with Ca = the concentration of CH3COOH = TO BE DETERMINED
⇒with Va = the volume of CH3COOH = 1.00 mL = 0.001L
⇒with a = the coefficient of CH3COOH = 1
⇒with Cb = the concentration of NaOH = 0.258 M
⇒with Vb = the volume of NaOH = 32.40 mL = 0.03240 L
Ca * 0.001 L = 0.258 * 0.03240
Ca = 8.36 M
The concentration of acetic acid is 8.36 M
The correct answer is 7 I just took the test :)
Molarity = moles of solute(HCl)
------------------------------------
volume of the solution
= 1
------
5
= 0.2M.
Hence option B is correct.
Hope this helps!!
Answer:
2
Explanation:
In two reactions energy is released.
1) C₆H₁₂O₆ + 6O₂ → 6H₂O + 6CO₂ + heat
It is cellular respiration reaction.It involves the breakdown of glucose molecule in the presence of oxygen to yield large amount of energy. Water and carbon dioxide are also produced as a byproduct.
Glucose + oxygen → carbon dioxide + water + 38ATP
2) 2H₂ + O₂ → 2H₂O ΔH = -486 kj/mol
The given reaction is formation of water. In this reaction oxygen and hydrogen react to form water and 486 kj/mol is also released.
The reaction in which heat is released is called exothermic reaction.
Exothermic reaction:
The type of reactions in which energy is released are called exothermic reactions.
In this type of reaction energy needed to break the bonds are less than the energy released during the bond formation.
For example:
Chemical equation:
C + O₂ → CO₂
ΔH = -393 Kj/mol
it can be written as,
C + O₂ → CO₂ + 393 Kj/mol
Endothermic reactions:
The type of reactions in which energy is absorbed are called endothermic reactions.
In this type of reaction energy needed to break the bond are higher than the energy released during bond formation.
For example:
C + H₂O → CO + H₂
ΔH = +131 kj/mol
it can be written as,
C + H₂O + 131 kj/mol → CO + H₂
Answer:
a) a = 3485 M⁻¹cm⁻¹
b) C = 0,000127 M
Explanation:
Lambert-Beer law says that there is a linear relationship between absorbance and concentration of a chemical substance. The formula is:
A = a×b×C
Where A is absorbance, a is molar absorptivity, b is path length and C is concentration.
a) In the problem Concentration is 0.0000792 M, b is 1,000cm and Absorbance is absorbance of sample-absorbance of blank: 0,341-0,065 = 0,276
Replacing:
0,276 = a×1,000cm×0,0000792M
<em>a = 3485 M⁻¹cm⁻¹</em>
b) As the experiment consist in the same compound in the same solvent, the molar absorptivity will be the same, a = 3485 M⁻¹cm⁻¹, path length will be 1,000cm and absorbance: 0,508-0,065 = 0,443
Replacing:
0,443 = 3485 M⁻¹cm⁻¹×1,000cm×C
<em>C = 0,000127 M </em>
<em></em>
I hope it helps!