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:
See the answer below
Explanation:
<em>The duration of flushing the eyes at the eyewash station in case of accidental contact with chemicals depends of the nature of the chemical.</em>
If the chemical is known to be a <u>non-irritant or mild-irritant</u> one, a <u>5-minute </u>washing time is recommended as the first aid. before seeking the help of a physician,
For <u>moderate to severe irritant</u> chemicals, an immediate <u>15-20 minutes</u> washing period is recommended before seeking further medical help.
For <u>corrosive and strong alkalis</u> chemicals, <u>30 and 60 minutes</u> washing are recommended respectively before seeking the attention of a physician.
However, if the nature of the chemical is unknown,<u> a minimum of 20-minutes washing is generally recommended</u> as first aid before seeking immediate medical help.
Answer: Balance
Explanation: Mass is the amount of matter contained in a body.