Answer:
3.00 mol
Explanation:
Given data:
Mass of P₄ = 211 g
Mass of oxygen = 240 g
Moles of P₂O₅ = ?
Solution:
Chemical equation:
P₄ + 5O₂ → 2P₂O₅
Number of moles of P₄:
Number of moles = mass/ molar mass
Number of moles = 211 g / 123.88 g/mol
Number of moles = 1.7 mol
Number of moles of O₂ :
Number of moles = mass/ molar mass
Number of moles = 240 g / 32g/mol
Number of moles = 7.5 mol
Now we will compare the moles of product with reactant.
O₂ : P₂O₅
5 : 2
7.5 : 2/5×7.5 = 3.00
P₄ : P₂O₅
1 : 2
1.7 : 2×1.7 = 3.4 mol
Oxygen is limiting reactant so the number of moles of P₂O₅ are 3.00 mol.
Mass of P₂O₅:
Mass = number of moles × molar mass
Mass = 3 mol ×283.9 g/mol
Mass = 852 g
The first one is 32mL and the second one is 2.62 and I think it’s grams/mL I’m not for sure about the letters on the second one
The molar mass of M is 0.225g/mol and the element M is Hydrogen
If a metal M combines with an oxygen element to form the oxide,
then the chemical reaction will be expressed as:

This shows that 4 moles of an unknown element M react with the oxygen element to produce the oxide
Given the following parameters
Mass of M = 0.890 grams
Mass of
= 0.956 grams
Get the molar mass of M:
Molar mass = Mass/number of moles
Molar mass = 0.890/4
Molar mass = 0.225g/mol
Hence the molar mass of M is 0.225g/mol and the element M is Hydrogen
Learn more here: brainly.com/question/6996520
Answer : The mass of sulfuric acid needed is
.
Solution : Given,
pH = 8.94
Volume of solution = 380 ml =

Molar mass of sulfuric acid = 98.079 g/mole
As we know,

![pOH=-log[OH^-]](https://tex.z-dn.net/?f=pOH%3D-log%5BOH%5E-%5D)
![5.06=-log[OH^-]](https://tex.z-dn.net/?f=5.06%3D-log%5BOH%5E-%5D)
![[OH^-]=0.00000871=8.71\times 10^{-6}mole/L](https://tex.z-dn.net/?f=%5BOH%5E-%5D%3D0.00000871%3D8.71%5Ctimes%2010%5E%7B-6%7Dmole%2FL)
Now we have to calculate the moles of
.
Formula used : 
![\text{ Moles of }[OH^-]=\text{ Concentration of }[OH^-]\times Volume\\\text{ Moles of }[OH^-]=(8.71\times 10^{-6}mole/L)\times (380\times 10^{-3}L)=3309.8\times 10^{-9}moles](https://tex.z-dn.net/?f=%5Ctext%7B%20Moles%20of%20%7D%5BOH%5E-%5D%3D%5Ctext%7B%20Concentration%20of%20%7D%5BOH%5E-%5D%5Ctimes%20Volume%5C%5C%5Ctext%7B%20Moles%20of%20%7D%5BOH%5E-%5D%3D%288.71%5Ctimes%2010%5E%7B-6%7Dmole%2FL%29%5Ctimes%20%28380%5Ctimes%2010%5E%7B-3%7DL%29%3D3309.8%5Ctimes%2010%5E%7B-9%7Dmoles)
For neutralization, equal number of moles of
ions will neutralize same number of
ions.
![\text{ Moles of }[OH^-]=\text{ Moles of }[H^+]=3309.8\times 10^{-9}moles](https://tex.z-dn.net/?f=%5Ctext%7B%20Moles%20of%20%7D%5BOH%5E-%5D%3D%5Ctext%7B%20Moles%20of%20%7D%5BH%5E%2B%5D%3D3309.8%5Ctimes%2010%5E%7B-9%7Dmoles)
As, 
From this reaction, we conclude that
2 moles of
ion is given by the 1 mole of 
moles of
ion is given by
moles of 
Now we have to calculate the mass of sulfuric acid.
Mass of sulfuric acid = Moles of
× Molar mass of sulfuric acid
Mass of sulfuric acid = 
Therefore, the mass of sulfuric acid needed is
.