Answer:
(1) 0.0016 mol/L
Explanation:
Let the concentration of alcohol after 3.5 hours be y M
The reaction follows a first-order
Rate = ky^0 = change in concentration/time
k = 6.4×10^-5 mol/L.min
Initial concentration = 0.015 M
Concentration after 3.5 hours = y M
Time = 3.5 hours = 3.5×60 = 210 min
6.4×10^-5y^0 = 0.015-y/210
y^0 = 1
0.015-y = 6.4×10^-5 × 210
0.015-y = 0.01344
y = 0.015 - 0.01344 = 0.00156 = 0.0016 mol/L (to 4 decimal places)
Answer: The millimoles of sodium carbonate the chemist has added to the flask are 256
Explanation:
Molarity is defined as the number of moles dissolved per liter of the solution.
To calculate the number of moles for given molarity, we use the equation:
.....(1)
Molarity of 
solution = 1.42 M
Volume of solution = 180.0 mL
Putting values in equation 1, we get:
Thus the millimoles of sodium carbonate the chemist has added to the flask are 256.
Ksp - solubility product constant is equivalent to equilibrium constant, except this constant is used to determine the solubility of ions of a solid in a solution.
ksp is the product of the soluble ions in the compound. Higher the ksp value, higher the degree of solubility.
ZnCO₃ (s) ---> Zn²⁺ (aq) + CO₃²⁻ (aq)
n n
ksp = [Zn²⁺][CO₃²⁻]
In the equation equal amounts of ions Zn²⁺ and CO₃²⁻ ions are soluble.
amount of ions soluble = n
ksp is therefore equal to;
ksp = n x n
ksp = n²
ksp = 1 * 10⁻¹⁰ M
therefore
1 * 10⁻¹⁰ M = n²
n = 1 x 10⁻⁵ M
therefore concentration of CO₃²⁻ = 1 x 10⁻⁵ M
NiCl₂ commonly forms a green aqueous solution.
Answer:
A = 674.33mmHg
B = 0.385atm
Explanation:
Both question A and B requires the application of pressure law which states that the pressure of a fixed mass of gas is directly proportional to its temperature provided that volume is kept constant.
Mathematically,
P = kT, k = P / T
P1 / T1 = P2 / T2 = P3 / T3 =.......= Pn/Tn
A)
Data:
P1 = 799mmHg
T1 = 50°C = (50 + 273.15) = 323.15K
P2 = ?
T2 = 273.15K
P1 / T1 = P2 / T2
Solve for P2
P2 = (P1 × T2) / T1
P2 = (799 × 273.15) / 323.15
P2 = 674.37mmHg
The final pressure is 674.37mmHg
B)
P1 = 0.470atm
T1 = 60°C = (60 + 273.15)K = 333.15K
P2 = ?
T2 = 273.15K
P1 / T1 = P2 / T2
Solve for P2,
P2 = (P1 × T2) / T1
P2 = (0.470 × 273.15) / 333.15
P2 = 0.385atm
The final pressure is 0.385atm
