Molar mass O2 = 31.99 g/mol
Molar mass CO2 = 44.01 g/mol
Moles ratio:
<span>C3H8 + 5 O2 = 3 CO2 + 4 H2O
</span>
5 x 44.01 g O2 ---------------- 3 x 44.01 g CO2
( mass of O2) ------------------ 37.15 g CO2
mass of O2 = 37.15 x 5 x 44.01/ 3 x 44.01
mass of O2 = 8174.8575 / 132.03
mass of O2 = 61.916 g
Therefore:
1 mole O2 ----------------- 31.99 g
moles O2 -------------------- 61.916
moles O2 = 61.916 x 1 / 31.99
moles = 61.916 / 31.99 => 1.935 moles of O2
The reactions based on the absorption and release of the energy are called endothermic and exothermic reactions. The reaction is exothermic.
<h3>What is an exothermic reaction?</h3>
Exothermic reactions are the reaction in which the reactant produces products that release energy from the system to the surroundings. In the reaction bond energy of the reactant is less than the product.
Energy from the system is released in the form of heat, sound, light and electricity. The weak bonds of the compounds are replaced with stronger ones and the standard enthalpy of the reaction is negative.
Therefore, option c. reaction is exothermic is correct.
Learn more about the exothermic reactions here:
brainly.com/question/26616927
Answer:

Explanation:
Hello,
In this case, since nitric acid is HNO₃ and strontium hydroxide is Sr(OH)₂ we can represent the balanced chemical reaction by equaling the atoms of strontium, nitrogen, oxygen and hydrogen at both reactants and products as shown below:

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