Complete Question:
Ions to calculate the p-values: Na⁺, Cl⁻, and NH₄⁺
Answer:
pNa = 0.307
pCl = 0.093
pNH₄ = 0.503
Explanation:
The p-value is calculated by the antilog of the concentration of the substance of interest. For example, pH = -log[H⁺]. Thus, first, let's find the ions concentration.
Both substances are salts that solubilize completely, thus, by the solution reactions:
NaCl → Na⁺ + Cl⁻
NH₄Cl → NH₄⁺ + Cl⁻
So, for both reactions the stoichiometry is 1:1:1 and the concentration of the ions is equal to the concentration of the salts.
[Na⁺] = 0.493 M
[Cl⁻] = 0.493 + 0.314 = 0.807 M
[NH₄⁺] = 0.314 M
The p-values are:
pNa = -log[Na⁺] = -log(0.493) = 0.307
pCl = -log[Cl⁻] = -log(0.807) = 0.093
pNH₄ = -log[NH₄⁺] = -log(0.314) = 0.503
Answer is: A. 1.1 3 1023 NiCl2 formula units.
m(NiCl₂) = 24.6 g; mass of nickel(II) chloride.
M(NiCl₂) = 129.6 g/mol; molar mass of nickel(II) chloride.
n(NiCl₂) = m(NiCl₂) ÷ M(NiCl₂).
n(NiCl₂) = 24.6 g ÷ 129.6 g/mol.
n(NiCl₂) = 0.19 mol; amount of nickel(II) chloride.
Na = 6.022·10²³ 1/mol; Avogadro constant.
N(NiCl₂) = n(NiCl₂) · Na.
N(NiCl₂) = 0.19 mol · 6.022·10²³ 1/mol.
N(NiCl₂) = 1.13·10²³; number of formula units.
Answer: measure the mass (48.425g) of KCl
Explanation:
To prepare the solution 0.65M KCl we must measure the mass of KCl that would be dissolved in 1L of the solution. This can be achieved by:
Molar Mass of KCl = 39 + 35.5 = 74.5g/mol
Number of mole (n) = 0.65
Mass conc of KCl = n x molar Mass
Mass conc of KCl = 0.65 x 74.5 = 48.425g
Therefore, to make 0.65M KCl, we must measure 48.425g
It is a combustion reaction. C3H8 will react with oxygen to form carbon dioxide and water.
Answer:
1) 0,081 ft/s
2) 0,746 lb/s
Explanation:
The relation between flow and velocity of a fluid is given by:
Q=Av
where:
- Q, flow [ft3/s]
- A, cross section of the pipe [ft2]
- v, velocity of the fluid [ft/s]
1)
To convert our data to appropiate units, we use the following convertion factors:
1 ft=12 inches
1 ft3=7,48 gallons
1 minute=60 seconds
So,
As the pipe has a circular section, we use A=πd^2/4:
Finally:
Q=vA......................v=Q/A
2)
The following formula is used to calculate the specific gravity of a material:
SG = ρ / ρW
where:
- ρ = density of the material [lb/ft3]
- ρW = density of water [lb/ft3] = 62.4 lbs/ft3
then:
ρ = SG*ρW = 1,49* 62,4 lb/ft3 = 93 lb/ft3
To calculate the mass flow, we just use the density of the chloroform in lb/ft3 to relate mass and volume:
