Answer:
Explanation:
Considering the Henderson- Hasselbalch equation for the calculation of the pH of the acidic buffer solution as:
![pH=pK_a+log\frac{[salt]}{[acid]}](https://tex.z-dn.net/?f=pH%3DpK_a%2Blog%5Cfrac%7B%5Bsalt%5D%7D%7B%5Bacid%5D%7D)
Given that:-
[Acid] = 0.12 M
Volume = 3.0 L
pKa = 3.74
pH = 5.30
So,
![5.30=3.74+log\frac{[sodium\ formate]}{0.12}](https://tex.z-dn.net/?f=5.30%3D3.74%2Blog%5Cfrac%7B%5Bsodium%5C%20formate%5D%7D%7B0.12%7D)
Solving, we get that:-
[Sodium formate] = 4.36 M
Considering:
So,
So, Moles of sodium formate = 4.36*3.0 moles = 13.08 moles
Molar mass of sodium formate = 68.01 g/mol
The formula for the calculation of moles is shown below:
Thus,
Answer:
4.84 × 10⁻⁶ M
Explanation:
First, we will calculate the partial pressure of Ar (pAr) using the following expression.
pAr = P × χAr
where,
P: total pressure
χAr: mole fraction
pAr = P × χAr
pAr = 0.370 atm × 9.34 × 10⁻³
pAr = 3.46 × 10⁻³ atm
We can find the solubility of Ar in water (S) using Henry's law.
S = kH × pAr
where
kH: Henry's constant
S = kH × pAr
S = 1.40 × 10⁻³ M/atm × 3.46 × 10⁻³ atm
S = 4.84 × 10⁻⁶ M
Answer: exothermic
Explanation: chemical reactions that release energy is called exothermic, and in this case, more energy is being released. (I THINK)
Answer: Molar mass is the amount grams that one mole weighs.
Explanation: You need to find the molar mass of NaCl which is the same as the amu on the periodic table in grams. So it is 22.99(Na) + 35.45(Cl) = 58.44
You also know that for every mole of NaCl you have 1 mole of Na because every molecule of NaCl has 1 atom of Na.
Finally, using the periodic table, again, you see that the molar mass of Na is 22.99.
Then using stoichiometry, you can find the grams of sodium.
100(g NaCl) * 1 mol (NaCl)/58.44 g (NaCl) * 1 mol (Na)/ 1 mol (NaCl) * 22.99 (g of Na)/ 1 mol (Na)
which equals 39.339435 g of Na.
If you need to maintain significant figures the answer will be 40.
Answer:
B. overlap of two d orbitals end to end overlap of p orbital.
Explanation:
Sigma bonds are the strongest type of bonds and they are covalent which is due to the direct or end to end overlap of orbitals. The symbol σ is used to adequately describe the bond that exists in a molecule.
In organic molecules, a single C-C bond is a sigma bond while a multiple C-C bond is composed of one sigma bond together with pi or other bonds that is a double bond has one sigma plus one pi bond, and a triple bond has one sigma plus two pi bonds.
Examples include: s-s orbital, pz-pz orbitals, dz-dz orbital and hybrids like sp-p etc.
