Answer:
0.804g of NaHCO₃ you must add
Explanation:
pKa of HCO₃⁻/CO₃²⁻ is 10.32.
It is possible to find pH of a buffer by using H-H equation, thus:
pH = pka + log [A⁻] / [HA]
<em>Where [HA] is concentration of acid (HCO₃⁻) and [A⁻] is concentration of conjugate acid (CO₃²⁻).</em>
Moles of CO₃²⁻ = K₂CO₃ are:
4.00g ₓ (1mol / 138.206g) = 0.0289 moles CO₃²⁻
Replacing:
10.80 = 10.32 + log [0.0289] / [HCO₃⁻]
[HCO₃⁻] = 0.009570 moles you need to add to obtain the desire pH
As molar mass of NaHCO₃ is 84.007g/mol, mass of NaHCO₃ is:
0.009570 moles ₓ (84.007g / mol) =
<h3>0.804g of NaHCO₃ you must add</h3>
It is an ideal gas therefore we can use the ideal gas equation to solve the problem. The ideal gas equation is expressed as PV = nRT. First, we solve the amount of the gas in moles using the said equation and the first conditions.
(2.0 atm) (5.0 x 10^3 cm^3) = n (82.0575 atm.cm^3/mol.K)(215 K)
n=0.5668 mol
Using the second conditions given, we obtain the new pressure.
P (4.0 x 10^3) = 0.5668 x <span>82.0575 x 265
P= 3.08 atm</span>
Answer:
Energy is neither created nor destroyed.
Explanation:
The law of conservation of energy states that energy can neither be created nor be destroyed. The total energy of an isolated system remains conserved. It never gets 0. It changes from one form of energy to other but never vanishes.
Hence, the correct option is (d) "Energy is neither created nor destroyed"
Answer:
R kelly math convinced me that macaroni noodles tastes like butt
Explanation:
R kelly - way of thinking
12 = 16
13 = 18
5 = 42
3 = 21
11 = 67