(8分)下列几组物质中,互为同位素的有__________,互为同素异形体的有________,互为同系物的有____________,互为同分异构体的有___________,属于同种物质的有__________。①O2和O3 ②35Cl和37Cl ③CH3CH3和CH3CH2CH3④CH3CH2CH(CH3)CH2CH3和CH3CH2CH(CH3)CH(CH3)CH3⑤氯仿和三氯甲烷⑥⑦CH3(CH2)2CH3和(CH3)2CHCH3 ⑧CH3CH(CH3)CH3和CH(CH3)3