This question is missing the part that actually asks the question. The questions that are asked are as follows:
(a) How much of a 1.00 mg sample of americium remains after 4 day? Express your answer using 2 significant figures.
(b) How much of a 1.00 mg sample of iodine remains after 4 days? Express your answer using 3 significant figures.
We can use the equation for a first order rate law to find the amount of material remaining after 4 days:
[A] = [A]₀e^(-kt)
[A]₀ = initial amount
k = rate constant
t = time
[A] = amount of material at time, t.
(a) For americium we begin with 1.00 mg of sample and must convert time to units of years, as our rate constant, k, is in units of yr⁻¹.
4 days x 1 year/365 days = 0.0110
A = (1.00)e^((-1.6x10^-3)(0.0110))
A = 1.0 mg
The decay of americium is so slow that no noticeable change occurs over 4 days.
(b) We can simply plug in the information of iodine-125 and solve for A:
A = (1.00)e^(-0.011 x 4)
A = 0.957 mg
Iodine-125 decays at a much faster rate than americium and after 4 days there will be a significant loss of mass.
Answer:
- <u>Yes,</u> <em>all titrations of a strong base with a strong acid have the same pH at the equivalence point.</em>
This <u>pH is 7.</u>
Explanation:
<em>Strong acids</em> and <em>strong bases</em> ionize completely in aqueous solutions. The ionization of strong acids produce hydronium ions, H₃O⁺, and the ionization of strong bases produce hydroxide ions, OH⁻.
Since the ionization of strong acids and bases progress until completion, there is not reverse reaction.
The definition of pH is pH = - log [H₃O⁺]. Acids have low pH (below 7, and greater than 0) and bases have high pH (above 7 and less than 14). Neutral solutions have pH = 7.
Acid-base titrations are a method to determine the concentration of an acid from the known concentration of a base, or the concentraion of a base from the known concentration of an acid.
The<em> equivalence point</em> of the titration is the point at which the the number of moles of hydronium ions and hydroxide ions are equal.
Then, at that point, the hydronium and hydroxide ions will be in the stoichiometric proportion to form a neutral solution, i.e. the pH of the solution wiill be 7.
Answer:
HOFO = (0, 0, +1, -1)
Explanation:
The formal charge (FC) can be calculated using the following equation:
<u>Where:</u>
V: are the valence electrons
N: are the nonbonding electrons
B: are the bonding electrons
The arrange of the atoms in the oxyacid is:
H - O₁ - F - O₂
Hence, the formal charge (FC) on each of the atoms is:
H: FC = 1 - 0 - 1/2*(2) = 0
O₁: FC = 6 - 4 - 1/2*(4) = 0
F: FC = 7 - 4 - 1/2*(4) = +1
O₂: FC = 6 - 6 - 1/2*(2) = -1
We can see that the negative charge is in the oxygen instead of the most electronegative element, which is the F. This oxyacid is atypical.
I hope it helps you!
Answer:
= konstanta produk kelarutan
= kation dalam larutan berair
= anion dalam larutan berair
= konsentrasi relatif a dan b
DARI WEB
Divide the mass of the compound by the mass of the solvent and then multiply by 100 g to calculate the solubility in g/100g . Solubility of NaNO3=21.9g or NaNO3 x 100 g/ 25 g =87.6. Calculate the molar mass of the dissolved compound as the sum of mass of all atoms in the molecule.
Answer: Water because if we say aqueous it means it resembles water or related to water.
