问题
选择题
下列溶液的pH大于7的是（ ）
A．石灰水
B．食盐水
C．食用醋
D．稀硫酸
答案
A、澄清石灰水是氢氧化钙的水溶液，呈碱性，其pH大于7，故选项正确；
B、食盐水呈中性，其pH等于7，故选项错误；
C、食用醋是醋酸的水溶液，呈酸性，其pH小于7，故选项错误；
D、稀硫酸呈酸性，其pH小于7，故选项错误．
故选A．
搜题请搜索小程序“爱下问搜题”
下列溶液的pH大于7的是（ ）
A．石灰水
B．食盐水
C．食用醋
D．稀硫酸
A、澄清石灰水是氢氧化钙的水溶液，呈碱性，其pH大于7，故选项正确；
B、食盐水呈中性，其pH等于7，故选项错误；
C、食用醋是醋酸的水溶液，呈酸性，其pH小于7，故选项错误；
D、稀硫酸呈酸性，其pH小于7，故选项错误．
故选A．
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One day, the Greys were walking in the countryside when Belinda, Mr. Grey's daughter, saw a little boy playing happily with a lovely dog in his yard. "How lovely the dog is! I want 1._________ a pet dog, too!" said Belinda to his parents. "But we live in the building. People who live in buildings 2._________ to keep pets," said Mrs. Grey. Belinda felt disappointed and cried 3.________. Suddenly, Mr. grey had an idea. He took Belinda to a toy shop. He went in and soon went out with a big box ." What's in the box ?" Little Belinda thought .After arriving home ,Belinda opened the box and found an electric dog .It could walk, bark and wag its tail like a real dog ! Belinda enjoyed 4._________ with it very much. Many things are not so nice as we think, but we can do something instead. It will still make 5._________ happy. |