Answer:
(3) 5.36
Explanation:
Since this is a titration of a weak acid before reaching equivalence point, we will have effectively a buffer solution. Then we can use the Henderson-Hasselbalch equation to answer this question.
The reaction is:
HAc + NaOH ⇒ NaAc + H₂O
V NaOH = 40 mL x 1 L/1000 mL = 0.040 L
mol NaOH reacted with HAc = 0.040 L x 0.05 mol/L = 0.002 mol
mol HAC originally present = 0.050 L x 0.05 mol/L = 0.0025 mol
mol HAc left after reaction = 0.0025 - 0.002 = 0.0005
Now that we have calculated the quantities of the weak acid and its conjugate base in the buffer, we just plug the values into the equation
pH = pKa + log ((Ac⁻)/(HAc))
(Notice we do not have to calculate the molarities of Ac⁻ and HAc because the volumes cancel in the quotient)
pH = -log (1.75 x 10⁻⁵) + log (0.002/0.0005) = 5.36
THe answer is 5.36
Answer:
See explanation
Explanation:
This conversion must go through a sequence of steps as i have shown in the image attached to this answer.
The acetone is converted to propan-2-ol using LiAlH4, THF and acid. The propan-2-ol may be converted to propene by E2 elimination. Addition of HBr yields 2-bromo propane.
The Wurtz reaction converts 2-bromo propane to 2,3- dimethyl butane. This can be brominated in the presence of light to yield 3-bromo-2,3-dimethyl butane. Elimination of HBr using a base leads to the formation of the required product as shown.
Manipulation of the independent variable should change the dependent variable, the value of which "depends" on the independent variable's change in value.
Answer:
True statment
2) Styrofoam would make a good calorimeter
3) Insulating material would make a good calorimeter
Explanation:
The calorimeter is one which is insulated that is which will not absorb or let the heat to escape from it. the calorimeter is used to measure the heat change during a process so if it will allow to exchange heat with surrounding it will deviate the readings or observence.
Copper is a good conductor of heat so we cannot use it make a calorimeter.
Hence
1) Copper would make a good calorimeter : False
2) Styrofoam would make a good calorimeter: True
Styrofoam is a bad conductor or insulator so it can be and it is used for calorimeter.
3) Insulating material would make a good calorimeter
: True
4) A good calorimeter should easily absorb heat : false
Answer:
121 K
Explanation:
Step 1: Given data
- Initial volume (V₁): 79.5 mL
- Initial temperature (T₁): -1.4°C
- Final volume (V₂): 35.3 mL
Step 2: Convert "-1.4°C" to Kelvin
We will use the following expression.
K = °C + 273.15 = -1.4°C + 273.15 = 271.8 K
Step 3: Calculate the final temperature of the gas (T₂)
Assuming ideal behavior and constant pressure, we can calculate the final temperature of the gas using Charles' law.
V₁/T₁ = V₂/T₂
T₂ = V₂ × T₁/V₁
T₂ = 35.3 mL × 271.8 K/79.5 mL = 121 K