1. ₉¹⁹F
2. Mg(OH)₂
3. 2H₂ + O₂ ⇒ 2H₂O
<h3>Further explanation</h3>
1. Fluorine, atomic number : 9 , mass number = 19
Symbol : ₉¹⁹F
protons=electrons=atomic number = 9
neutrons = mass number - atomic mass

Configuration : [He] 2s² 2p⁵
2. Magnesium hydroxide is an ionic compound and is a strong base consisting of 2 ions:
Positive ion: Magnesium: Mg²⁺
negative ion: Hydroxide: OH⁻
The charges of the two are crossed, so that the compound becomes:
Mg(OH)₂
3. Reaction :
H₂ + O₂ --------> H₂O
give coefficient :
aH₂ + bO₂ --------> H₂O
H, left = 2a, right 2⇒2a=2⇒a=1
O, left = 2b, right 1⇒2b=1⇒b=0.5
Reaction becomes :
H₂ + 0.5O₂ --------> H₂O x 2
2H₂ + O₂ --------> 2H₂O
The half-life of the substance is 3.106 years.
<h3>What is the formula for exponential decay?</h3>
- The exponential decline, which is a rapid reduction over time, can be calculated with the use of the exponential decay formula.
- The exponential decay formula is used to determine population decay, half-life, radioactivity decay, and other phenomena.
- The general form is F(x) = a.
Here,
a = the initial amount of substance
1-r is the decay rate
x = time span
The equation is given in its correct form as follows:
a =
×
As this is an exponential decay of a first order reaction, t is an exponent of 0.8.
Now let's figure out the half life. Since the amount left is half of the initial amount at time t, that is when:
a = 0.5 a0
<h3>Substituting this into the equation:</h3>
0.5
=
×
0.5 = 
taking log on both sides
t log 0.8 = log 0.5
t = log 0.5/log 0.8
t = 3.106 years
The half-life of the substance is 3.106 years.
To learn more about exponential decay formula visit:
brainly.com/question/28172854
#SPJ4
Detrivores; i.e, Earth Worms, Rolly Pollies etc.
Answer:
<h2>1093750 J</h2>
Explanation:
The kinetic energy of an object can be found by using the formula

v is the velocity
m is the mass
From the question we have

We have the final answer as
<h3>1,093,750 J</h3>
Hope this helps you