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In numbering carbon atoms in the parent chain of a hydrocarbon, why would you number from right to left, rather than left to right

Acontainer holds 35.8 moles of gas under 10.0 atm of pressure at 70.0 c. what is the volume of the container?

The following reaction shows sodium carbonate reacting with calcium hydroxide. na2co3 + ca(oh)2 → naoh + caco3 how many grams of naoh are produced from 20.0 grams of na2co3? (molar mass of na = 22.989 g/mol, c = 12.01 g/mol, o = 15.999 g/mol, ca = 40.078 g/mol, h = 1.008 g/mol) 12.2 grams 15.1 grams 24.4 grams 30.2 grams