Answer: The ratio of carbon dioxide molecules to oxygen molecules is 20 :31
Explanation:
Combustion is a chemical reaction in which hydrocarbons are burnt in the presence of oxygen to give carbon dioxide and water.
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The balanced combustion reaction is,:

Thus the ratio of carbon dioxide molecules to oxygen molecules is 20 : 31
Answer:
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Explanation:
To answer this question a balanced chemical equation is necessary. The correct equation is: N2 + 3H2 = 2NH3
From this equation, one mole of nitrogen react with 3 moles of hydrogen to give 2 moles of ammonia.
Therefore, the mole ratio of NH3 to N2 is 2:1
Answer: when the temperature is increased, the number of collisions per second increases.
Explanation:
the rate of collisions and the temperature is directly proportional. If the energy of the gas particles is boosted by using the temperature, the chances of the particles bumping into each other due to the high energy increases, thus increasing the number of collisions. This also increases the rate of reaction. Thus when temperature is increased the number of collisions also increases.