Answer:
Volume
Explanation:
Density:
Density is equal to the mass of substance divided by its volume. In order to find the density of earth when mass is given we have to calculate its volume. The volume of earth is calculated by using the volume formula for sphere. i.e 4/3 π r³. we also require radius to find the volume and we know that
Diameter = 2 × radius
The diameter of earth equator is 12756.75 Km. So we calculate the radius by dividing the diameter by 2. Then by putting the value of radius in 4/3 π r³ we will get the volume and then we can calculate the density of earth.
Units:
SI unit of density is Kg/m3.
Other units are given below,
g/cm3, g/mL , kg/L
Formula:
D=m/v
D= density
m=mass
V=volume
Symbol:
The symbol used for density is called rho. It is represented by ρ. However letter D can also be used to represent the density.
We assume that we have Ka= 4.2x10^-13 (missing in the question)
and when we have this equation:
H2PO4 (-) → H+ + HPO4-
and form the Ka equation we can get [H+]:
Ka= [H+] [HPO4-] / [H2PO4] and we have Ka= 4.2x10^-13 & [H2PO4-] = 0.55m
by substitution:
4.2x10^-13 = (z)(z)/ 0.55
z^2 = 2.31x 10^-13
z= 4.81x10^-7
∴[H+] = 4.81x10^-7
when PH equation is:
PH= -㏒[H+]
= -㏒(4.81x10^-7) = 6.32
Answer:
V = 2.32 Liters
Explanation:
PV = nRT => V = nRT/P
n = 25.8g/122g/mole = 0.21 mole
R = 0.08206 L·atm/mol·K
T = 25.44°C + 273 = 298.44K
P = 2.22 atm (given in problem)
V = (0.21mol)(0.08206 L·atm/mol·K)(298.44K)/(2.22atm) = 2.32 Liters at 25.44°C & 2.22atm
(3.5mol)(24.106 g/1mol c6h6) =84.371 g C6H6
