A:室温下,氨水与氯化铵的pH=7的混合溶液中:c(Cl﹣)=c(NH4+)
B:向NaHCO3溶液中加入少量NaOH固体,可抑制HCO3﹣的水解,使c(HCO3﹣)增大
C:0.1 mol•L﹣1的(NH4)2SO4溶液中:c(NH4+)>c(SO42﹣)>c(H+)>c(OH﹣)
D:常温下,等体积pH=a的醋酸与pH=b的NaOH溶液恰好中和时,a+b=14
下列哪种现象不是生物对环境的适应( )
我国境内目前已确认的最早的古人类是( )
I think life will be different in the future. People 1live under the sea or on the moon. They can fly to the moon in a short time 2 spaceship. People will travel to other planets too. Robots will3all the housework for people. They can even take care 4 babies for people. No one will 5newspapers. All the people "see" news with a pair of special glasses.
南宋时广州成为全国第一大港。
错误:____改正:____。
阅读下面这段文字,根据拼音写出汉字。
人!他总是一面前进,一面用心血浇guàn____那艰难、孤独而又豪迈的zhēng____途,用胸中灼热的鲜血创造出永不diāo____谢的诗歌的花朵,他巧妙地把发自不安的心灵中的苦闷呼声谱成乐曲,他根据自身的经验创造科学,每走一步都把人生装点得更加美好,就像太阳那样慷kǎi____地用它的光芒把大地普照。