Answer:
C6H6
Explanation:
We can obtain the molecular formula from the empirical formula.
What we need do here is:
(CH)n = 78
The n shows the multiples of both element present in the actual compound. It can be seen that carbon and hydrogen have the same element ratio here. We then use the atomic masses of both elements to get the value of n. The atomic mass of carbon is 12 a.m.u while the atomic mass of hydrogen is 1 a.m.u
(1 + 12)n = 78
13n = 78
n = 78/13 = 6
The molecular formula is
(CH)n = (CH)6 = C6H6
Answer:
-179.06 kJ
Explanation:
Let's consider the following balanced reaction.
HCl(g) + NaOH(s) ⟶ NaCl(s) + H₂O(l)
We can calculate the standard enthalpy change for the reaction (ΔH°r) using the following expression.
ΔH°r = 1 mol × ΔH°f(NaCl(s)) + 1 mol × ΔH°f(H₂O(l)) - 1 mol × ΔH°f(HCl(g)) - 1 mol × ΔH°f(NaOH(s))
ΔH°r = 1 mol × (-411.15 kJ/mol) + 1 mol × (-285.83 kJ/mol) - 1 mol × (-92.31 kJ/mol) - 1 mol × (-425.61 kJ/mol)
ΔH°r = -179.06 kJ
Answer:
Protein Concentration is 2.82mg/L
Explanation:
According to Beer-Lambert's Law, Absorbance is directly proportional to the concentration.
However, the concentration of a solution can be determined from a calibration curve, in which Absorbance is plotted on the y-axis and the Concentration on the x-axis.
Plotting the best line, the equation of line is used
y = mx + c
where y is absorbance = 0.150
m is slope = 0.0163
x is concentration
c is intercept = 0.104
inserting the values from the question
y = mx + c
0.150 = 0.0163x + 0.104
0.0163x = 0.150 - 0.104
0.0163x = 0.046
Divide both sides by 0.0163
0.0163x/0.0163 = 0.046/0.0163
x = 2.82
Concentration of protein = 2.82 mg/L
The pH of a solution which is 0.023 m in weak base and 0 037 m in the conjugate weak acid whose Ka= 7.1 × 10⁻⁶ is 4.93.
pH determines the amount of hydrogen and hydroxide ions in a solution. It is the negative logarithm of hydrogen ion concentration.
Given,
Ka= 7.1 × 10⁻⁶
Weak base = 0.023M
Acid = 0.037M
Using base dissociation constant, Ka we can calculate pKa by:
pKa = -log [Ka]
pKa = -log [7.1 × 10⁻⁶]
pKa = 5.15
A weak base and its conjugate acid are present in equal proportions in buffer solution. Using the Henderson-Hasselbalch equation, we can find out the pH of a buffer solution that constitutes a weak base and its conjugate acid.
Using Henderson-Hasselbalch equation,
pH = pKa + log [Weak base / acid]
pH = 5.15 + log [0.023 / 0.037]
pH = 5.15 + log[0.6]
pH = 5.15 - 0.22
pH = 4.93
Therefore, the pH of the solution is 4.93.
Learn more about pH here, brainly.com/question/22390063
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75 x 3 = ______
Well if you take 75 plus 75 you get 150 Fish ,Then you add 75 more so 150 plus 75 equals 225 So there are 225 fish in display at the entrance.
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