The radioisotope U-238 is primarily used in dating geologic formation. This method is used for dating sediments from either a marine or playa lake environment. Because this method is used for the period between 100,000 years and 1,200,000 years before the present, it aids in bridging the gap between the carbon-14 dating method and the potassium-argon dating method.
Answer:
32.6%
Explanation:
Equation of reaction
2KClO₃ (s) → 2KCl (s) + 3O₂ (g)
Molar mass of 2KClO₃ = 245.2 g/mol ( 122.6 × 2)
Molar volume of Oxygen at s.t.p = 22.4L / mol
since the gas was collected over water,
total pressure = pressure of water vapor + pressure of oxygen gas
0.976 = 0.04184211 atm + pressure of oxygen gas at 30°C
pressure of oxygen = 0.976 - 0.04184211 = 0.9341579 atm = P1
P2 = 1 atm, V1 = 789ml, V2 = unknown, T1 = 303K, T2 = 273k at s.t.p
Using ideal gas equation
=
V2 =
V2 = 664.1052 ml
245.2 yielded 67.2 molar volume of oxygen
0.66411 will yield =
= 2.4232 g
percentage of potassium chlorate in the original mixture =
= 32.6%
Answer:
See explanation below
Explanation:
In an electrochemical cell, electricity is obtained by the gradual deterioration of the anode.
Hence, surface area of the metal will affect the length of time within which the electrochemical cell works.
The greater the surface area of the metal, the longer the electrochemical cell can function and the greater the quantity of electricity produced, hence the answer above.
Answer:
The correct answer is 10.939 mol ≅ 10.94 mol
Explanation:
According to Avogadro's gases law, the number of moles of an ideal gas (n) at constant pressure and temperature, is directly proportional to the volume (V).
For the initial gas (1), we have:
n₁= 1.59 mol
V₁= 641 mL= 0.641 L
For the final gas (2), we have:
V₂: 4.41 L
The relation between 1 and 2 is given by:
n₁/V₁ = n₂/V₂
We calculate n₂ as follows:
n₂= (n₁/V₁) x V₂ = (1.59 mol/0.641 L) x 4.41 L = 10.939 mol ≅ 10.94 mol