A: carbon
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A diagram of a biogas generator is shown. The gas, if collected, can be used as a fuel. However, if the gas is allowe…
Ozone molecules are continually being broken down and formed in the upper atmosphere.
Which pollutant causes eutrophication in rivers?
Which graph shows the number of electrons in the outer shell of an atom, plotted against the proton (atomic) number f…
Which pair of elements, when combined together, do not form a covalent compound?
The diagram shows the structure of a covalent compound containing the element hydrogen, H, and the unknown elements X…