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:
A_____PENCIL______ consists of a mixture of graphite powder (a form of carbon) and clay that is baked and hardened and encased in wood or paper. a. silverpoint b. pencil c. charcoal d. chalk e. paste
Explanation:
A pencil is a writing material, where the graphite is what gives the black color to the writing stroke.
Answer:
C. Fluorine because the model has 9 protons which is represented by the atomic number
Explanation:
We usually identify an element by the number of protons in them. The number of protons is the atomic number of an atom.
- Every atom has a specific number of protons in them.
- This number of protons is the atomic number.
- According to the periodic law, atoms are arranged on the periodic table based on their atomic number.
- The given fluorine atom has 9 protons which represents the atomic number of the atom.
- This way, the given number clearly shows the right model for identifying the chemical specie.
Answer:
For instance equation C6H5C2H5 + O2 = C6H5OH + CO2 + H2O will not be balanced, but PhC2H5 + O2 = PhOH + CO2 + H2O will; Compound states [like (s) (aq) or (g)] are not required. If you do not know what products are enter reagents only and click 'Balance'. In many cases a complete equation will be suggested.
Explanation:
Explanation:
Solubility is defined as a property of solutes by virtue of which they get dissolved in a favorable solvent. The solute can only be dissolved in any suitable solvent up to a limit at a given temperature. This is a characteristic of the the solute-solvent pairing.