Answer:
The mass percent of sulfur is 9.98%.
Explanation:
<em>The percentage of sulfur in coal can be determined by burning a sample of the solid and passing the resulting sulfur dioxide gas into a solution of hydrogen peroxide, which oxidizes it to sulfuric acid, and then titrating the acid.</em>
The corresponding balanced equations are:
S + O₂ ⇄ SO₂ [1]
SO₂ + H₂O₂ ⇄ H₂SO₄ [2]
H₂SO₄ + 2 NaOH ⇄ Na₂SO₄ + 2 H₂O [3]
First, we have to calculate how many moles of NaOH we have.
n = 0.114 mol/L × 0.441 L = 0.0502 mol
Then, we will use the following relations:
- According to [3], 2 moles of NaOH react with 1 mole of H₂SO₄
- According to [2], 1 mole of H₂SO₄ is produced per mole of SO₂
- According to [1], 1 mole of SO₂ is produced per mole of S
- The molar mass of S is 32.0 g/mol
Then, for 0.0502 moles of NaOH:
If there are 0.803 g of S in an 8.05 g sample, the mass percent of sulfur is:
Answer:
Examples of compounds that contain only covalent bonds are methane (CH4), carbon monoxide (CO), and iodine monobromide (IBr). Covalent bonding between hydrogen atoms: Since each hydrogen atom has one electron, they are able to fill their outermost shells by sharing a pair of electrons through a covalent bond.
Explanation:
Answer:
V₂ = 4.7 L
Explanation:
Given data:
Initial volume = 5.0 L
Initial pressure = 1.50 atm
Final pressure = 1240 mmHg (1240/760 = 1.6 atm)
Final volume = ?
Solution:
P₁V₁ = P₂V₂
V₂ = P₁V₁ / P₂
V₂ = 1.50 atm ×5.0 L/1.6 atm
V₂ = 7.5 atm. L /1.6 atm
V₂ = 4.7 L
Here,
Heat gain by the first sample of water + Heat lost by the second sample of water is equal to zero (0).
Now, Mass of water sample one = 108 g (given)
Mass of water sample two = 66.9 g (given)
Temperature for water sample one =
Let, temperature for water sample two =x
And, final temperature =
Now,
where, = final temperature
= initial temperature
Substitute all the given values in above formula:
[tex x =84.81^{0}C [/tex]
A. The mass of one mole of the virus is calculated by multiplying the mass of a single virus by the Avogadro's number which is equal to 6.022 x 10^23. Performing this operation,
mass = (9.0 x 10^-12 mg)(6.022 x 10^23) = 5.42 x 10^12 mg
In correct number of significant figures, the answer would only have to be 5.4 x 10^12 mg.
b. The number of moles of the virus that will have the same mass as the oil tanker is calculated by dividing the mass of the oil tanker by the mass of one mole of the virus. Note that doing division, both would have to have the same units.
n = (3.0 x 10^7 kg) / (5.4 x 10^12 mg)(1 g/1000 mg)(1 kg/1000 g)
Simplifying,
n = 6
In correct number of significant figures, the answer is 6.0.