Following chemical reaction is involved upon titration of Ca(OH)2 with HCl,
Ca(OH)2 + 2HCl ↔ CaCL2 + 2H2O
Above is an example of acid-base titration to generate salt and water. Here, H+ ions of acid (HCl) combines with OH- (ions) of base [Ca(OH)2] to generated H2O
Given,
concentration of HCl = 0.0199 M
Total volume of HCl consumed during titration = 16.08 mL = 16.08 X 10^(-3) L
∴, number of moles of H+ consumed = Molarity X Vol. of HCl (in L)
= 0.0199 X 16.08 X 10^(-3)
= 3.1999 X 10^-4 mol
Thus, total number of moles of [OH-] ions present initial = 3.1999 X 10-4 mol
So, initial conc. [OH-] ion = ![\frac{number of moles of [OH-]}{volume of solution (L)}](https://tex.z-dn.net/?f=%20%5Cfrac%7Bnumber%20of%20moles%20of%20%5BOH-%5D%7D%7Bvolume%20of%20solution%20%28L%29%7D%20)
=

= 0.03199 M
White phosphorus melts and then vaporizes at high temperatures. The gas effuses at a rate that is 0.404 times that of neon in the same apparatus under the same conditions-There are 4 atoms of P in the molecule
Explanation:
Ar=30,97g/mol
/
=
=0,404
0,404=
=20,18/30,97*x
X=20,18/30,97*0,163
X=4
There are 4 atoms of P in the molecule
White phosphorus melts and then vaporizes at high temperatures. The gas effuses at a rate that is 0.404 times that of neon in the same apparatus under the same conditions-There are 4 atoms of P in the molecule
<u>Answer:</u> The correct answer is Option A.
<u>Explanation:</u>
Mole ratio is defined as the ratio between the stoichiometric coefficients of the molecules present in the chemical reaction.
For the given balanced chemical equation:

By Stoichiometry of the reaction:
3 moles of iron metal reacts with 4 moles of water to produce 1 mole of iron oxide and 4 moles of hydrogen gas.
The mole ratio of 
Hence, the correct answer is Option A.
The new pressure : P₂ = 1038.39 mmHg
<h3>Further explanation</h3>
Given
1.5 L container at STP
Heated to 100 °C
Required
The new pressure
Solution
Conditions at T 0 ° C and P 1 atm are stated by STP (Standard Temperature and Pressure).
So P₁ = 1 atm = 760 mmHg
T₁ = 273 K
T₂ = 100 °C+273 = 373 K
Gay Lussac's Law
When the volume is not changed, the gas pressure is proportional to its absolute temperature

Input the value :
P₂=(P₁.T₂)/T₁
P₂=(760 x 373)/273
P₂ = 1038.39 mmHg
See attachement for the answer to your question.