Heres the best help i can give you There is a couple different ways to determine if a bond is ionic or covalent. By definition, an ionic bond is between a metal and a nonmetal, and a covalent bond is between 2 nonmetals. So you usually just look at the periodic table and determine whether your compound is made of a metal/nonmetal or is just 2 nonmetals
Answer:
b) 3.10
Explanation:
HF ⇄ H
+ + F
Using Henderson-Hasselbalch Equation:
pH = pKa + log [A-]/[HA].
Where;
pKa = Dissociation constant = -log Ka
Hence, pKa of HF = -log 7.2 x 10^-4 = 3.14266
[A-] = concentration of conjugate base after dissociation = moles of base/total volume
= 0.15 x 0.3/0.8
= 0.05625 M
[HA] = concentration of the acid = moles of acid/total volume
= 0.10 x 0.5/0.8
= 0.0625 M
Note: <em>Total volume = 500 + 300 = 800 mL = 0.8 dm3</em>
pH = 3.14266 + log [0.05625/0.0625]
= 3.14267 + (-0.04575749056)
= 3.09691250944
<em>From all the available options below:</em>
<em>a) 2.97
</em>
<em>b) 3.10
</em>
<em>c) 3.19
</em>
<em>d) 3.22
</em>
<em>e) 3.32</em>
The correct option is b.
Answer:
i think the first one is gravity and second one is rotation
Explanation:
#1. An element or ion that has lost two electrons must have a net charge of 2+, because it has two more protons than electrons, therefore the answer is Mg2+
#2. aluminum ions have an oxidation state of 3+ and fluoride has an oxidation state of 1-, therefore I’m order for the charges to cancel you need 3 fluoride ions.
Therefore, the answer is AlF3
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 .
