Answer:There are total 118 elements in world as about marbale
Explanation:
<span>A. Exact ecological footprints are often difficult to calculate, but estimates can be useful in comparing populations.
</span>Which of the following could be said about ecological footprints? <u /> <u>Exact ecological footprints are often difficult to calculate, but estimates can be useful in comparing populations.</u><u />
NOT:
b. Ecological footprints can't be used to determine carrying capacity.
C. Ecological footprints don't take into account resources needed to absorb and manage wastes.
<span>D. The average ecological footprints for various countries are nearly identical.</span>
Precipitation hope this helped you
To completely convert 9. 0 moles of hydrogen gas (h2) to ammonia gas, 3.0 moles of nitrogen gas (n2) are required.
<h3>What are moles?</h3>
The mole is a SI unit of measurement that is used to calculate the quantity of any substance.
<h3 />
The given reaction is 
By the stoichiometry rule of ratio hydrogen: nitrogen
3 : 1
The reacted moles of nitrogen is equals to H/3 moles of reacted hydrogen
So, moles of nitrogen

Thus, 3.0 moles of nitrogen gas (n2) are required.
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