Answer: 1.63 moles
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number of particles.
To calculate the moles, we use the equation:
Given mass = 223 g
Molar mass = 136.4
Thus there are 1.63 moles in 223 g of the compound.
Answer:
4.76
Explanation:
In this case, we have to start with the buffer system:
We have an acid () and a base (). Therefore we can write the henderson-hasselbach reaction:
If we want to calculate the pH, we have to calculate the pKa:
According to the problem, we have the same concentration for the acid and the base 0.1M. Therefore:
If we divide:
If we do the Log of 1:
So:
With this in mind, the pH is 4.76.
I hope it helps!
Answer:
Saturated.
Explanation:
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Animal fats are lipids derived from animals which are commonly solid at room temperature and mainly constituted by triglycerides which are strictly chemically saturated with hydrogen, it means they do not tend to have double or triple bonded carbon atoms but just single-bonded carbons. This fact suggests that animal fats provide more energy than vegetable fats because they have more C-H bonds that when broken increase the total provided energy.
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The quantity of acetic acid that is needed to prepare the 500 mL buffer is 9.0075 grams.
Given the following data:
First of all, we would write the equilibrium chemical reaction for acetate-acetic acid as follows:
Next, we would calculate HA by applying Henderson-Hasselbalch equation:
Where:
Substituting the given parameters into the formula, we have;
For the concentration of both acids, we have:
For acetate ion:
At a volume of 0.5 liters, we have:
By stoichiometry:
Total moles = = 0.15 moles.
Mass = 9.0075 grams.
Read more on moles here: brainly.com/question/3173452
Answer:
You will need 9,0 g of acetic acid
Explanation:
The equilibrium acetate-acetic acid is:
CH₃COOH ⇄ CH₃COO⁻ + H⁺ pka = 4,76
Using Henderson-Hasselbalch you will obtain:
pH = pka + log₁₀
Where HA is acetic acid and A⁻ is acetate ion
4,90 = 4,76 + log₁₀
1,38 = (1)
As acetate concentration is 0,300M:
0,300M = [HA] + [A⁻] (2)
Replacing (2) in (1):
[HA] = 0,126 M
And:
[A⁻] = 0,174 M
As you need to produce 500 mL:
0,5 L × 0,126 M = 0,063 moles of acetic acid
0,5 L × 0,174 M = 0,087 moles of acetate
To produce moles of acetate from acetic acid:
CH₃COOH + NaOH → CH₃COO⁻ + Na⁺ + H₂O
Thus, moles of acetate are equivalents to moles of NaOH and all acetates comes from acetic acid, thus:
0,087 moles of acetate + 0,063 moles of acetic acid ≡ 0,15 moles of acetic acid × = 9,0 g of acetic acid
I hope it helps!
Answer: D
Explanation:
Km value is a signature of the enzyme. It is the characteristic feature of a particular enzymes for a specific substrate. Km denotes the affinity of the enzyme for substrate. The lesser the numerical value of Km, the affinity of the enzyme for the substrate is more.
In the velocity x substrate graph in a fixed quantity if enzyme. As substrate concentration is increase, the velocity is also increasing at the initial phase but the curve fatten afterwards. This is because as more substrate is added, all enzymes molecules become saturated. Further increase in substrate cannot make any effect in the reaction velocity.
The maximum velocity is called Vmax. Km is the concentration of substrate that Vmax is half.
The larger the numerical value of Km, the lesser the enzyme binds the substrate
Onoble gases
O halogens
O transitional metals
Group/Family 18 on the periodic table is called the noble gases.
Group/Family 18 on the periodic table is called the noble gases. The noble gases are a group of chemical elements that have full valence electron shells, which makes them stable and nonreactive. This group includes elements like helium, neon, argon, krypton, xenon, and radon.
OB. only the important elements that exist in the world.
OC. only the important compounds that exist in the world.
OA. all the known elements that exist in the world today.