The structure of this 27-carbon compound suggests a complex biosynthetic pathway, but all of its carbon atoms are provided by a single precursor—_______. A: formic acid B: acetate C: propionate D: pyruvate

How many tons of carbon were released in 2010? A: 27 gigatons B: 37 gigatons C: 31 gigatons D: 17 gigatons

Carbon chains can rotate around a double bond (carbon=carbon or C=C).

What caused the deposits A: The hydrochloric acid broke the carbon bonds in tile carbon dioxide, B: The magnesium oxide broke the carbon oxygen bonds in the carbon dioxide. C: The burning magnesium broke the carbon oxygen bonds in the carbon dioxide. D: The gas collection method broke the carbon-oxygen bonds in the carbon dioxid

______ of agricultural practices is a recognized method of carbon sequestration as soil can act as an effective carbon sink offsetting as much as 20% of 2010 carbon dioxide emissions annually.

The synonym of CO2 is .（ ）。 A: hydrogen B: carbon monoxide C: carbon dioxide D: oxygen

Carbon dioxide consists of carbon and （ ） A: oxygen B: emergency C: upgrade D: religious

are very soft ,and can be used for bolts and for machine parts that do not need strength.: Alloy steels|High carbon steels|Low carbon steels|Medium carbon steels

carbon emission

carbon dioxide