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 formula for tht is C8H8O4
Chemistry is the branch of science that deals with the identification of the substances of which matter is composed the investigation of their properties and the ways in which they interact, combine, and change and the use of these processes to form new substances.
It is actually a Colloid, which means it will never mix and settle.<span />
Answer:
V = 11.21 L
Explanation:
Given data:
Volume of helium = ?
Number of moles = 0.500 mol
Temperature = 273.15 K
Pressure of gas = 1 atm
Solution:
Formula:
PV = nRT
R = general gas constant = 0.0821 atm.L/ mol.K
V = nRT/P
V = 0.500 mol × 0.0821 atm.L/ mol.K × 273.15 K / 1 atm
V = 11.21 L / 1
V = 11.21 L
