Answer:
2.15 mg of uranium-238 decays
Explanation:
For decay of radioactive nuclide-

where N is amount of radioactive nuclide after t time,
is initial amount of radioactive nuclide and
is half life of radioactive nuclide
Here
,
and 
So,
so, N = 2.446 mg
mass of uranium-238 decays = (4.60-2.446) mg = 2.15 mg
Answer:
Radiation is energy. It can come from unstable atoms that undergo radioactive decay, or it can be produced by machines. Radiation travels from its source in the form of energy waves or energized particles. There are different forms of radiation and they have different properties and effects.
Explanation:
Sorting the chemical elements in order from least reactive to most reactive, we have:
1. Fluorine (F).
2. Arsenic (As).
3. Antimony (Sb).
4. Silicon (S).
<u>Given the following chemical elements:</u>
Reactivity can be defined as a chemical property which determines how readily a chemical element <u>bonds</u> with other chemical elements, in order to form a new chemical compound.
Generally, the ability of a chemical element to bond with other chemical elements is largely (highly) dependent on the number of valence electrons it has in the outermost shell of its atomic nucleus.
As a general rule, chemical elements that are having <u>fewer</u> number of valence electrons are the most reactive while those having <u>higher</u> valence electrons are least reactive.
Also, chemical reactivity <u>decreases</u> down a group on the periodic table.
Based on the periodic table, the valency for the given chemical elements are:
- <u>Antimony (Sb):</u> 5 valence electrons.
- <u>Silicon (S):</u> 4 valence electrons.
- <u>Fluorine (F):</u> 7 valence electrons.
- <u>Arsenic (As):</u> 5 valence electrons.
In conclusion, sorting the chemical elements in order from least reactive to most reactive, we have:
1. Fluorine (F).
2. Arsenic (As).
3. Antimony (Sb).
4. Silicon (S).
Find more information: brainly.com/question/18214726
a. 381.27 m/s
b. the rate of effusion of sulfur dioxide = 2.5 faster than nitrogen triiodide
<h3>Further explanation</h3>
Given
T = 100 + 273 = 373 K
Required
a. the gas speedi
b. The rate of effusion comparison
Solution
a.
Average velocities of gases can be expressed as root-mean-square averages. (V rms)

R = gas constant, T = temperature, Mm = molar mass of the gas particles
From the question
R = 8,314 J / mol K
T = temperature
Mm = molar mass, kg / mol
Molar mass of Sulfur dioxide = 64 g/mol = 0.064 kg/mol

b. the effusion rates of two gases = the square root of the inverse of their molar masses:

M₁ = molar mass sulfur dioxide = 64
M₂ = molar mass nitrogen triodide = 395

the rate of effusion of sulfur dioxide = 2.5 faster than nitrogen triodide