First we have to find Ka1 and Ka2
pKa1 = - log Ka1 so Ka1 = 0.059
pKa2 = - log Ka2 so Ka2 = 6.46 x 10⁻⁵
Looking at the values of equilibrium constants we can see that the first one is really big compared to second one. so, the pH will be affected mainly by the first ionization of the acid.
Oxalic acid is H₂C₂O₄
H₂C₂O₄ ⇄ H⁺ + HC₂O₄⁻
0.0356 M 0 0
0.0356 - x x x
Ka1 =
![\frac{[H^+][HC2O4^-]}{[H2C2O4]}](https://tex.z-dn.net/?f=%20%5Cfrac%7B%5BH%5E%2B%5D%5BHC2O4%5E-%5D%7D%7B%5BH2C2O4%5D%7D%20)
= x² / 0.0356 - x
x = 0.025 M
pH = - log [H⁺] = - log (0.025) = 1.6
Answer:

Explanation:
Given that:-
Pressure = 
The expression for the conversion of pressure in Pascal to pressure in atm is shown below:
P (Pa) =
P (atm)
Given the value of pressure = 43,836 Pa
So,
=
atm
Pressure = 6.80977 atm
Volume =
= 2.3 L ( 1 m³ = 1000 L)
n = 2 mol
Using ideal gas equation as:
PV=nRT
where,
P is the pressure
V is the volume
n is the number of moles
T is the temperature
R is Gas constant having value = 0.0821 L.atm/K.mol
Applying the equation as:
6.80977 atm × 2.3 L = 2 mol × 0.0821 L.atm/K.mol × T
⇒T = 95.39 K
The expression for the kinetic energy is:-

k is Boltzmann's constant =
T is the temperature
So, 

Answer:
can't be done
Explanation:
protons and electrons always are the same number,and the neutrons are found by subtracting the atomic mass and protons/electrons soooooooo it can't have 15 protons, 18 electrons, and 18 neutrons.......i hope this helped if not please tell me.
Answer:
a) the atomic number is 15
b) the mass number is 15+16 = 31
c) element is phosphorus
d)Group 15 period 3