Answer: 
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 for butane is,:

The isotopes are elements with the same number of protons but different number of neutrons.
Boron atomic number is 5. That is the number of protons.
The natural occurring isotopes of boron contain 5 or 6 neutrons. Other, non stable isotopes, contain from 1 to 16 neutrons.
Answer:
uhh if it's 16 hours into minutes then the answer is 690 minutes
but if its not im sorry ;w;
Answer: Scientists use the term bioenergetics to describe the concept of energy flow (Figure 4.2) through living systems, such as cells. Cellular processes such as the building and breaking down of complex molecules occur through stepwise chemical reactions. Some of these chemical reactions are spontaneous and release energy, whereas others require energy to proceed. Just as living things must continually consume food to replenish their energy supplies, cells must continually produce more energy to replenish that used by the many energy-requiring chemical reactions that constantly take place. Together, all of the chemical reactions that take place inside cells, including those that consume or generate energy, are referred to as the cell’s metabolism.
Answer:
the answer is A
Explanation:
because abiotic things are non-living things