Answer:
B and C
Explanation:
When we have to do a buffer solution we always have to choose the reaction that has the <u>pKa closer to the desired pH value</u>. When we find the pKa values we will obtain:
![pKa_1=-Log[6.9x10^-^3]=2.16](https://tex.z-dn.net/?f=pKa_1%3D-Log%5B6.9x10%5E-%5E3%5D%3D2.16)
![pKa_2=-Log[6.2x10^-^8]=7.20](https://tex.z-dn.net/?f=pKa_2%3D-Log%5B6.2x10%5E-%5E8%5D%3D7.20)
![pKa_3=-Log[4.8x10^-^13]=12.31](https://tex.z-dn.net/?f=pKa_3%3D-Log%5B4.8x10%5E-%5E13%5D%3D12.31)
The closer value is pKa2 with a value of 7.2. Therefore we have to use the second reaction. In which 
is the <u>acid</u> and 
is the <u>base</u>. Therefore the answer for the first question is B and the answer for the second question is C.
The volume of titanium with mass of 0. 10g and density of 4. 51 g/cm³ is 0. 02 cm³
<h3>
What is volume?</h3>
Volume is known to be equal to the mass divided by the density.
It is written thus:
Volume = Mass / density
<h3>
How to calculate the volume</h3>
The volume is calculated using the formula:
Volume = mass ÷ density
Given the mass = 0. 10g
Density = 4.51 g/cm³
Substitute the values into the formula
Volume of titanium = 0. 10 ÷ 4.51 = 0. 02 cm³
Thus, the volume of titanium with mass of 0. 10g and density of 4. 51 g/cm³ is 0. 02 cm³
Learn more about volume here:
brainly.com/question/1762479
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Secrets undiscovered is correct, but this chemical formula is not balanced. Double check your question to make sure
