X equals <span>2.76923076923</span>
Given :
A compound has a molar mass of 129 g/mol .
Empirical formula of compound is C₂H₅N .
To Find :
The molecular formula of the compound.
Solution :
Empirical mass of compound :

Now, n-factor is :

Multiplying each atom in the formula by 3 , we get :
Molecular Formula, C₆H₁₅N₃
IF magnesium sulfide reacts with oxygen in the air it will produce
magnesium oxide + sulfur (IV) oxide
<u><em>explanation</em></u>
magnesium sulfide burn in oxygen to produce magnesium oxide and sulfur (iv) oxide according to the equation below
2MgS +3O2 →2MgO +2SO2
that is 2 moles of MgS react with 3 moles of O2 to produce 2 moles of MgO and 2 moles of SO2
The arrows that represent the phase transitions in which heat energy is gained is : (A). 1, 2 and 3
<h3>Meaning of phase transitions</h3>
Phase transitions can be defined as the changing of matter from one form to another due to the addition or gaining of heat or due to the removal or loss of heat.
Phase transitions in matter are majorly between three phases which are: Solid, Liquid and Gas.
In conclusion, The arrows that represent the phase transitions in which heat energy is gained is : (A). 1, 2 and 3
Learn more about Phase transitions: brainly.com/question/11048831
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