在2A+3B=C+4D的反應(yīng)中,已知68gA與40gB恰好完全反應(yīng),生成24gC,若A物質(zhì)的相對(duì)分子質(zhì)量為136,試求D物質(zhì)的相對(duì)分子質(zhì)量是多少?
由題意,68gA與40gB恰好完全反應(yīng),生成24gC,則同時(shí)生成D的質(zhì)量為:68g+40g-24g=84g,
設(shè)D物質(zhì)的相對(duì)分子質(zhì)量是x,
2A+3B=C+4D
272 4x
68g 84g
= x=84.
答:D物質(zhì)的相對(duì)分子質(zhì)量是84.