题目

Plants are very important living things. Life could not go on if there were no plants. This is because plants can make food from air, water and sunlight. Animals and man cannot make food from air, water and sunlight. Animals get their food by eating plants and other animals. Therefore animals and man need plants in order to live. This is why we find that there are so many plants around us. If you look carefully at the plants around you, you will find that there are two kinds of plants: flowering plants and non-flowering plants. Flowering plants can make seeds. The seeds are prot常温下,下列各组离子在指定溶液中能大量共存的是A. pH=1的溶液中:Fe2+、NO、SO、Na+B. 由水电离的c(H+)=1×10-14mol·L-1的溶液中:Ca2+、K+、Cl-、HCOC. c(H+)/c(OH-)=1012的溶液中:NH、Al3+、NO、Cl-D. c(Fe3+)=0.1 mol·L-1的溶液中:K+、ClO-、SO、SCN-
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