> as lemmas
isopentane
isopentane n.
Brit. 
/ˌʌɪsə(ʊ)ˈpɛnteɪn/
, /ˌʌɪsə(ʊ)ˈpɛnteɪn/U.S. /ˌaɪsəˈpɛnˌteɪn/
2-methylbutane, (CH3)2CHCH2CH3, a volatile liquid hydrocarbon present in petroleum./ˌaɪsəˈpɛnˌteɪn/ΘΚΠ
the world > matter > chemistry > organic chemistry > hydrocarbons > [noun] > alkanes > branched-chain
isobutane1876
isoparaffin1876
isopentane1876
phytane1907
isooctane1909
pristane1923
triptane1943
1876 Encycl. Brit. V. 558/2 Iso~pentane..is formed by the dehydration of amyl alcohol by means of zinc chloride.
1943 V. A. Kalichevsky Amazing Petroleum Industry iv. 55 Natural gasoline contains certain quantities of a hydrocarbon known as isopentane which is a valuable component of high-grade gasolines.
1964 J. D. Roberts & M. Caserio Basic Princ. Org. Chem. iii. 92 The chlorination of isopentane at 300° gives all four possible monosubstitution products.
<
as lemmas