<span>Hydroelectric energy uses the movement of water to spin a turbine and produce electricity. Coal is a fossil fuel that is burned as an energy source, which results in emissions such as carbon dioxide, nitrogen, and sulfur. Coal use is associated with waste products both from the mining process to acquire the coal and also from the actual use of coal itself. Hydroelectric energy does not involve waste, but does pose potential problems to waterways. Coal use is more common than the use of hydroelectric energy.</span>
Answer:
2
Explanation:
There are some basic laws that guide the combination of elements chemically. These are the law of conservation of mass, law of definite proportion, law of multiple proportion and the law of reciprocal proportion.
For this question, the useful law to use is the law of definite proportion. Here, it is stated that no matter the method of preparation or source of preparation, the elements of a chemical compound are always present in a fixed ratio.
What this means that at any point in time, the compound titanium dioxide contains one atom of titanium and two atoms of oxygen. This means that both atoms are present at all times in a proportion of 1 to 2 .
The answer to this is 22, confirmed by gradpoint