2025年高职单招《化学》每日一练试题05月25日

<p class="introTit">判断题</p><p>1、钙铁锌硒都是微量元素。（）  </p><p>答 案：错</p><p>解 析：钙元素是人体的常量元素，铁、锌、硒是人体必需的微量元素，故此说法错误。</p><p>2、《物质构成的奥秘》告诉我们：元素的种类、化学性质分别与中子数、最外层电子数密切相关。（）  </p><p>答 案：错</p><p>解 析：元素是质子数相同的一类原子的总称，元素的种类与质子数密切相关；最外层电子数相同，化学性质相似，化学性质与最外层电子数密切相关，故错误。</p><p>3、淀粉经过消化，最终变化为能被小肠吸收的葡萄糖。（）  </p><p>答 案：错</p><p>解 析：淀粉首先在口腔内，被口腔内的唾液淀粉酶初步消化成麦芽糖，再在小肠内被最终消化成葡萄糖，葡萄糖易溶于水，被小肠吸收进入血液循环系统。</p><p class="introTit">单选题</p><p>1、某同学在点燃蜡烛时,提出固体石蜡可能变成蒸气才能燃烧。就此看法而言,应属于科学探究环节中的（）  </p><ul><li>A：提出问题</li><li>B：猜想与假设</li><li>C：进行实验</li><li>D：获得结论</li></ul><p>答 案：B</p><p>解 析：根据题意,某同学在点燃蜡烛时,提出固体石蜡可能变成蒸气才能燃烧,属于科学探究环节中的猜想与假设环节。故选 B。    </p><p>2、下列无色溶液，离子在溶液中不能大量共存的是（）  </p><ul><li>A：<img 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' /></li><li>B：<img src='https://img2.meite.com/questions/202307/1864b604b0e7338.png' /></li><li>C：<img src='https://img2.meite.com/questions/202307/1864b604b2a663f.png' /></li><li>D：<img src='https://img2.meite.com/questions/202307/1864b604b489d7a.png' /></li></ul><p>答 案：C</p><p>解 析：A、三种离子不反应，且无色，能大量共存，A不符合题意；B、三种离子不反应，且无色，能大量共存，B不符合题意；C、三种离子均为无色，氢离子和碳酸根离子生成水和二氧化碳气体，不能共存，C符合题意；D、铜离子为蓝色，D不符合题意；故选C。</p><p>3、已知某物质的化学式为 MgF₂,其中 F元素的化合价为-1价,那么该化合物中 Mg 元素的化合价为（）  </p><ul><li>A：+1</li><li>B：-1</li><li>C：+2</li><li>D：-2</li></ul><p>答 案：C</p><p>解 析：某物质的化学式为MgF₂,其中F元素的化合价为-1价,设化合物中 Mg 元素的化合价为x，x+(-1)×2=0,x=+2,则该化合物中 Mg 元素的化合价为+2 价。故选 C。    </p><p class="introTit">多选题</p><p>1、下列说法中不正确的是（）  </p><ul><li>A：酸和碱都含有氢元素</li><li>B：生成盐和水的反应一定是中和反应</li><li>C：多数酸和碱有腐蚀性</li><li>D：酸和碱能与所有的盐发生复分解反应</li></ul><p>答 案：BD</p><p>解 析：A、酸中含有氢离子，碱中含有氢氧根离子，宏观来看都含氢元素，故A说法正确；B、中和反应是指酸和碱生成盐和水的反应，生成盐和水的反应不一定是中和反应，如氧化铁和盐酸反应生成氯化铁和水，也生成盐和水，但不是中和反应，故生成盐和水的反应不一定是中和反应，故B说法不正确；C、多数酸和碱都有腐蚀性，故C说法正确；D、复分解反应的条件是生成物中必须有沉淀、或水、或气体生成，所以并不是酸和碱能与所有的盐发生复分解反应，例如硝酸钾和盐酸就不反应，故D说法不正确。故选BD。</p><p>2、下列事实遵守质量守恒定律的是___________(选填字母编号)。  </p><ul><li>A：10g水受热变成10g水蒸气</li><li>B：蜡烛燃烧变短</li><li>C：酒精久置变轻</li><li>D：在一定条件下，石墨转化为金刚石</li></ul><p>答 案：BD</p><p>解 析：质量守恒定律是指参加化学反应的各物质的质量总和等于反应后生成各物质的质量总和。A、10g水受热变成10g水蒸气,发生的是物理变化，不符合。B、蜡烛燃烧后生成了二氧化碳和水,两者会散失到空气中,所以质量变小,遵守质量守恒定律。C、酒精久置变轻了,只是酒精的状态发生改变,没有新物质生成,属于物理变化,不能用质量守恒定律解释。D石墨转化为金刚石,发生的是化学变化,遵循质量守恒定律.故选BD</p><p>3、CuCl₂溶液有时呈黄色，有时呈绿色或蓝色，这是因为在CuCl₂的水溶液中存在如下平衡：欲使溶液由绿色变为蓝色，可采用的方法是（） <img src="https://img2.meite.com/questions/202307/1864b64f836db84.png" /></p><ul><li>A：加NaCl溶液</li><li>B：加水</li><li>C：加AgNO₃溶液</li><li>D：加NaOH溶液</li></ul><p>答 案：BC</p><p>解 析：欲使溶液变成蓝色,则平衡向逆反应方向移动;A、加入氯化钠溶液,氯离子浓度增大,平衡正向进行,溶液呈绿色,A项错误;B、加水平衡逆向进行,溶液呈蓝色,B项正确;C、加AgNO₃溶液,银离子和氯离子结合生成氯化银沉淀,平衡逆向进行,溶液呈蓝色,C项正确;D、加NaOH溶液,氢氧根离子结合水合铜离子生成氢氧化铜沉淀,溶液不能变化为蓝色,D项错误;答案选BC。</p><p class="introTit">简答题</p><p>1、稀硫酸除铁锈的化学方程式为__________，充分反应后溶液呈________色。  </p><p>答 案：Fe₂O₃+3H₂SO₄=Fe₂（SO₄）₃+3H₂O；黄色</p><p>解 析：硫酸除铁锈，铁锈的主要成分氧化铁，和硫酸反应生成硫酸铁和水，对应的化学方程式为：Fe₂O₃+3H₂SO₄=Fe₂（SO₄）₃+3H₂O；硫酸铁溶液是黄色，所以观察到溶液由无色变成黄色</p>