Answer:
1.9 L
Explanation:
Step 1: Given data
- Initial number of moles of air (n₁): 4.0 mol
- Initial volume of the balloon (V₁): 2.5 L
- Final number of moles of air (n₂): 3.0 mol
- Final volume of the balloon (V₂): ?
Step 2: Calculate the final volume of the balloon
According to Avogadro's law, the volume of an ideal gas is directly proportional to the number of moles. We can calculate the final volume of the balloon using the following expression.
V₁ / n₁ = V₂ / n₂
V₂ = V₁ × n₂ / n₁
V₂ = 2.5 L × 3.0 mol / 4.0 mol
V₂ = 1.9 L
<u>Answer:</u> The correct answer is the mass number of the most common isotope of the element is 24.
<u>Explanation:</u>
We are given:
An element having atomic number 12 is magnesium and atomic mass of the element is 24.305
The image corresponding will be 
The number '24.305' is the average atomic mass of magnesium element.
Average atomic mass is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.
Formula used to calculate average atomic mass follows:

Average atomic mass of magnesium = 24.305 amu
As, the average atomic mass of magnesium lies closer to the mass of Mg-24 isotope. This means that the relative abundance of this isotope is the highest of all the other isotopes.
The 'Mg-24' isotope is the most common isotope of the given element.
Hence, the correct answer is the mass number of the most common isotope of the element is 24.
Answer
:
Flammable substances
Explanation
:
<em>Flammable substances</em> will catch fire and continue to burn when they contact an ignition source like a spark or a flame.
For example, <em>methanol</em> is a flammable liquid.
A flammable solid may also catch fire through friction. <em>Matches</em> are flammable solids.
"Only electrons are involved in chemical reactions" is the statement among the following choices given in the question that is the <span>best explanation for chemical reactions not to produce radioactive particles. The correct option among all the options that are given in the question is the third option or option "C". </span>
Answer:
vapour pressure I's crushing the bottle
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