ِAnswer:
1- The molarity of HCOOH = 9.515 M.
2- The mole fraction of HCOOH = 0.18.
Explanation:
<em>1- The molarity of HCOOH:</em>
- We can calculate the molarity of HCOOH using the relation:
M = (10pd)/molar mass.
p is the percent by mass of HCOOH = 35.9 %.
d is the specific gravity of HCOOH = 1.22 g/cm³.
Molar mass of HCOOH = 46.03 g/mol.
∴ M = (10pd)/molar mass = (10)(35.9 %)(1.22 gcm³) / (46.03 g/mol) = 9.515 M.
<em>2- The mole fraction of HCOOH:</em>
- We can suppose that we have a 100 g solution, that contains 35.9 g of HCOOH and 64.1 g of water.
<em>The mole fraction of HCOOH = (no. of moles of HCOOH) / (no. of moles of HCOOH + no, of moles of water).</em>
no. of moles of HCOOH = mass / molar mass = (35.9 g)/(46.03 g/mol) = 0.78 mol.
no. of moles of water = mass / molar mass = (64.1 g)/(18.0 g/mol) = 3.56 mol.
- The mole fraction of HCOOH = (no. of moles of HCOOH) / (no. of moles of HCOOH + no, of moles of water) = (0.78 mol) / (0.78 mol + 3.56 mol) = 0.18.
Answer:
C₇H₁₁N
Explanation:
To find the chemical formula, first, let's evaluate the given conditions.
1. <u>Is a primary amine</u>:
This means that the amine is connected to a carbon, like NH₂-R
2. <u>The degree of unsaturation of the five-membered carbon ring is equal to three</u>:
One of the degrees of unsaturation is for the five-membered carbon ring, the other two are for pi-bonds. This means that the five-membered carbon ring has 2 pi-bonds inside.
3. <u>There are seven carbon atoms</u>:
Five of these seven carbons are for the carbon ring and the other two are bonded to the primary amine.
From all of the above, we have that the chemical formula is:
C₅H₅-C₂H₄-NH₂ = C₇H₁₁N
I hope it helps you!
<em>Calculate the pH of the following substances formed during a volcanic eruption:
</em>
<em>• Acid rain if the [H +] is 1.9 x 10-5
</em>
<em>• Sulfurous acid if [H +] = 0.10
</em>
<em>• Nitric acid if [H +] = 0.11</em>
<em />
<h3>Further explanation </h3>
pH is the degree of acidity of a solution that depends on the concentration of H⁺ ions. The greater the value the more acidic the solution and the smaller the pH.
pH = - log [H⁺]
![\tt pH=-log[1.9\times 10^{-5}]\\\\pH=5-log1.9\\\\pH=4.72](https://tex.z-dn.net/?f=%5Ctt%20pH%3D-log%5B1.9%5Ctimes%2010%5E%7B-5%7D%5D%5C%5C%5C%5CpH%3D5-log1.9%5C%5C%5C%5CpH%3D4.72)
![\tt pH=-log[10^{-1}]\\\\pH=1](https://tex.z-dn.net/?f=%5Ctt%20pH%3D-log%5B10%5E%7B-1%7D%5D%5C%5C%5C%5CpH%3D1)
![\tt pH=-log[11\times 10^{-2}]\\\\pH=2-log~11=0.959](https://tex.z-dn.net/?f=%5Ctt%20pH%3D-log%5B11%5Ctimes%2010%5E%7B-2%7D%5D%5C%5C%5C%5CpH%3D2-log~11%3D0.959)
Answer:
hydrogen
Explanation:
The gas with the least molecular weight effuses the fastest (Graham's Law). Hence, H gas has a higher rate of diffusion compared to N, O, and Cl.
So, Cl is the slowest when it comes to the rate of diffusion, because it has the highest molecular weight.
Fishes yes according to the age, reptiles yes
