Answer:
Coal is classified as a nonrenewable energy source because it takes millions of years to form. Coal contains the energy stored by plants that lived hundreds of millions of years ago in swampy forests.
Given:
Diprotic weak acid H2A:
Ka1 = 3.2 x 10^-6
Ka2 = 6.1 x 10^-9.
Concentration = 0.0650 m
Balanced chemical equation:
H2A ===> 2H+ + A2-
0.0650 0 0
-x 2x x
------------------------------
0.065 - x 2x x
ka1 = 3.2 x 10^-6 = [2x]^2 * [x] / (0.065 - x)
solve for x and determine the concentration at equilibrium.
The system is isothermal, so we use the formula:
(delta)G = (delta)H - T (delta) S
Plugging in the given values:
(delta)G = -220 kJ/ mol - (1000K) (-0.05 kJ/mol K)
(delta)G = -170 kJ/mol
If we take a basis of 1 mol, the answer is
D. -170 kJ
Answer:
Mass = 785.9 g
Explanation:
Given data:
Atoms of gold = 2.4 × 10²⁴ atoms
Mass of gold = ?
Solution:
First of all we will convert the number of atoms into moles.
2.4 × 10²⁴ atoms × 1 mol/ 6.02 × 10²³ atoms
number of moles = 3.99 mol
Now we will determine the mass of gold.
Mass = number of moles × molar mass
Mass = 3.99 mol × 196.97 g/mol
Mass = 785.9 g
