<u>Answer:</u> The cross-sectional area of the cylindrical rod is 
<u>Explanation:</u>
We are given a cylindrical rod whose cross-sectional area will be in the form of circle.
To calculate the area of circle, we use the equation:
where,
r = radius of the rod = 
(Conversion factor: 1 m = 1000 mm)
Putting values in above equation, we get:
Hence, the cross-sectional area of the cylindrical rod is
I'm thinking its answer choice D. But it might be a good idea to wait and see if someone agrees
Answer:
no it is a ionic compound
Answer:
- <u><em>Option D. has a great [OH⁻]</em></u>
Explanation:
1) Both <em>acids</em> and <em>bases</em> ionize in aqueous solutions so they are able to <em>conduct electricity</em>.
The ions, being charged particles, when flow through the solution are charge carriers, then they conduct electricity.
So, the option A does not state a difference between a solution of a base and a solution of an acid.
2) Both acids and bases are able to cause an <em>indicator color change</em>.
The usufulness of the indicators is that they are able to change of color when the pH changes either from acid to basic or from basic to acid. There are different indicators because none is suitable for the whole range of pH, but the statement B is not how solutions of base and acids differ.
3) The model of Arrhenius for acids and bases states that an acid is a substance that ionizes in water releasing H⁺ ions (this is equivalent to H₃O⁺) and a base is a substance that releases OH⁻ ions in water. Then, acids have a greater concentration of H₃O⁺ (so option C is not true for a solution of a base) and bases have a greater concentraion of OH⁻, making the option D. true.
Answer: The number of moles of 
reacted was 0.229
Explanation:
According to ideal gas equation:
P = pressure of gas = Total pressure - vapor pressure of water = (749 - 23.8) mm Hg= 725.2 mm Hg = 0.954 atm (760mmHg= 1atm)
V = Volume of gas = 5.87 L
n = number of moles = ?
R = gas constant =
T =temperature =
According to stoichiometry:
1 mole of 
is produced by = 1 mole of
Thus 0.229 moles of is produced by = 
moles of
Thus number of moles of reacted was 0.229
