Answer:
Yes, Democritus's atomic theory was correct.
Explanation:
He thought the first part of his theory states that all matter is made of atoms, which are indivisible. The second part of the theory says all atoms of a given element are identical in mass and properties. The other scientists added onto his theory to show that he was correct, except Aristotle, he thought the world was made of the 4 elements: earth, wind, fire, water.
<h2>The answers are

and

</h2>
Explanation:
Given -
a) The molecular formula of ethylene glycol -

∴ The empirical formula of ethylene glycol will be -

Given -
b) The molecular formula of per-oxo-disulfuric acid (a compound used in bleaching agents) -

∴ The empirical formula of per-oxo-disulfuric acid will be -

Hence, the answers are
and
.
I will solve this question assuming the reaction equation look like this:
<span>MnO2 + 4 HCl ---> MnCl2 + Cl2 + 2 H2O.
</span>
For every one molecule of MnO2 used, there will be one molecule of Cl2 formed. If the molecular mass of MnO2 is 87g/mol and molecular mass of Cl2 is <span> 73.0 g/mol, the mass of MnO2 needed would be:
Cl mass/Cl molecular mass * MnO2 molecular mass=
25g/ (73g/mol) * (87g/mol) * 1/1= 29.8 grams</span>
Answer : The correct option is, the negative log of the hydroxide ion concentration.
Explanation :
pOH : It is defined as the negative logarithm of hydroxide ion concentration. It is a measure of the alkalinity of the solution.
Formula used :
![pOH=-log[OH^-]](https://tex.z-dn.net/?f=pOH%3D-log%5BOH%5E-%5D)
is the concentration of
ions.
When pOH is less than 7, the solution is alkaline.
When pOH is more than 7, the solution is acidic.
When pOH is equal to 7, the solution is neutral.
Answer:
The measure of angle ABE is 27°.
Explanation:
Consider the below figure attached with this question.
Given information: ∠ABE=2n+7 and ∠EBF=4n-13.
From the below figure it is clear that ∠ABE and ∠EBF are congruent.


Isolate variable terms on one side.


Divide both sides by 2.

The value of n is 10.
We need to find the measure of ∠ABE.

Therefore, the measure of angle ABE is 27°.