在反應(yīng)A+B═C+D中,已知25g A與10g B恰好完全反應(yīng)生成5g C.當(dāng)反應(yīng)有6g D生成時(shí),參加反應(yīng)的A是( ?。?br/>A. 10g
B. 5g
C. 20g
D. 25g
根據(jù)質(zhì)量守恒定律,反應(yīng)A+B═C+D中,25g A與10g B恰好完全反應(yīng)生成5g C時(shí)生成D物質(zhì)質(zhì)量=25g+10g-5g=30g,則反應(yīng)中物質(zhì)A、D的質(zhì)量比=25g:30g=25:30;
則當(dāng)反應(yīng)有6g D生成時(shí),參加反應(yīng)的A質(zhì)量=
×25=5g
故選:B.