Since the enthalpy can be calculated from the heat of formation, the enthalpy is 136 kJ/mol.
<h3>What is enthalpy?</h3>
The enthalpy of a reaction is the heat that is lost or gained in that reaction. We know that the enthalpy can be calculated from the heat of formation.
Thus, we can obtain the enthalpy of the reaction as 4 * 34 kJ/mol = 136 kJ/mol.
Learn more about enthalpy:brainly.com/question/13996238
#SPJ1
The answer is 1/16.
Half-life is the time required for the amount of a sample to half its value.
To calculate this, we will use the following formulas:
1.

,
where:
<span>n - a number of half-lives
</span>x - a remained fraction of a sample
2.

where:
<span>

- half-life
</span>t - <span>total time elapsed
</span><span>n - a number of half-lives
</span>
So, we know:
t = 10 min
<span>

= 2.5 min
We need:
n = ?
x = ?
</span>
We could first use the second equation to calculate n:
<span>If:

,
</span>Then:

⇒

⇒

<span>
</span>
Now we can use the first equation to calculate the remained fraction of the sample.
<span>

</span>⇒

<span>⇒

</span>
<em>Answer:</em>
<em>Ello mate ! the answer is super simple it's option "A" Fe</em>
<em>Explanation:</em>
<em>Iron is a chemical element with symbol</em><em> "Fe"</em><em> and atomic number 26. It is a type of metal, that belongs to the first transition series and group 8 of the periodic table. It is by mass the most common element on Earth, forming much of Earth's outer and inner core.</em>
Answer:
to go against dangerous viral and bacteria
Explanation: