酸性、碱性和中性盐
盐通过酸和碱之间的反应结晶,因此,我们应该预期水中的盐溶液对酸测试是中性的。尽管许多水手的水溶液是中性的(pH 值为 7),但一些盐在水中非物质化时会产生酸性或引入性结果(碱性溶液)。Salt Solution pH Nature Sodium Chloride Solution 7 Neutral Ammonium Chloride Solution 6 Acidic Sodium Carbonate Solution 9 Basic
氯化钠水溶液呈中性,氯化铵水溶液呈酸性,而碳酸钠水溶液呈碱性(或碱性)。在盐水解的基础上,可以揭开一些盐溶液的酸性和碱性
强酸和强碱的盐产生中性溶液
让我们抓住氯化钠的例子来推断这一点。氯化钠盐 (NaCl) 由强酸盐酸 (HCl) 和强碱氢氧化钠 (NaOH) 结晶而成。由于氯化钠是由强酸和强碱形成的,因此氯化钠的水溶液是中性的。它对酸性测试没有任何作用。
产生中性溶液的盐的另一个例子是硫酸钾 (K 2 SO 4 ) 它由强酸硫酸 (H2SO4) 和强碱氢氧化钾 (KOH) 固化而成
强酸和弱碱的盐产生酸性溶液
让我们以氯化铵为例。氯化铵 (NH 4 Cl) 是强酸盐酸 (HCl) 和弱碱氢氧化铵 (NH 4 OH) 的盐,因此氯化铵的水溶液具有酸性。这可以如下揭开神秘面纱。
When ammonium chloride is dissolved in water, it gets hydrolyzed to some extent to form ammonium hydroxide and hydrochloric acid :
NH4Cl (s) + H₂O (l) ⭢ NH4OH(aq) + HCI (aq)
where, Ammonium hydroxide (NH4OH) is a Strong acid and Hydrochloric acid (HCI) is a Weak base.
盐酸是一种完全电离的强酸,会产生大量的氢离子 (H(aq))。另一方面,氢氧化铵是一种弱碱,仅轻微电离并产生少量氢氧根离子 (OH – (aq))。由于氯化铵结果含有比氢氧根离子更多的氢离子,因此它本质上是酸性的。它将蓝色酸性测试变为红色。产生酸性溶液的盐的另一个例子是硫酸铵 (NH 4 ) 2 SO 4 。它由强酸硫酸(H 2 SO 4 )和弱碱氢氧化铵(NH 4 OH)形成。
弱酸和强碱的盐提供介绍性解决方案
让我们以碳酸钠为例。碳酸钠 (Na 2CO 3 ) 是弱酸性碳酸 (H 2 CO 3 ) 和强碱氢氧化钠 (NaOH) 的盐,因此碳酸钠水溶液将是元素性质的(或碱性性质的)。这可以解释如下。
碳酸钠在水中脱物质时,会发生一定程度的水解,生成氢氧化钠和碳酸
Na2CO3 (s) + 2H2O (l) ⭢ 2NaOH (aq) + H2CO3 (aq)
where, Sodium Hydroxide (NaOH) is a Strong base and Carbonic acid (H2CO3) is a weak acid.
氢氧化钠是一种强碱,可完全电离并产生大量氢氧根离子 (OH – (aq))。另一方面,碳酸是一种弱酸,几乎不能完全电离,因此会产生易碎的氢离子量 (H + (aq))。由于碳酸钠溶液含有比氢离子更多的氢氧根离子,因此它本质上是碱性的(或本质上是碱性的)。将红色酸性测试变为蓝色 另一个产生碱性溶液(或碱性溶液)的盐的例子是乙酸钠(CH 3 COONa)。它由弱酸乙酸 (CH 3 COOH) 和强碱氢氧化钠 (NaOH) 结晶而成。
示例问题
问题1:当将溶液添加到香草精中时,也无法检测到香草的区别香气。说明给出的溶液是酸还是碱。
回答:
When Hydrochloric acid reacts with an functional metal (like zinc), we observe that gas brimmed bubbles are solidified on the face of the metal Pass the gas formed through cleanser solution. Also, bring around a burning candle near the gas filed cleaner bubble if the gas present in bubble streamlets with a ‘pop’ sound, also its hydrogen gas.
问题 2:您将如何测试盐酸与功能金属反应时释放的气体?
回答:
Carbon dioxide (CO₂) gas is elaborated during the reaction. We transfer this gas through lime water which tums milky because of the CO₂ dissolution through it.
问题3:什么是嗅觉指标?说出两个嗅觉指针。邻接氢氧化钠溶液对这些嗅觉指针有什么影响?
回答:
Those essentialities whose aroma (or odour) fluctuations in acidic or basic solutions are called olfactory pointers Onion and vanilla excerpts are olfactory pointers When a basic solution like sodium hydroxide result is added to a cloth strip acted with onions (or onion excerpt), also the onion smell can not be detected.
问题4:酸与香精反应一般会放出哪种气体?你将如何测试这种气体的存在?
回答:
Hydrogen gas is liberated when an acid reacts with a metal. When reaction between an acid and a metal occurs, We observe the arrangement of gas bubbles. When these gas bubbles are handed over through cleaner(soup) solution, gas filled cleaner bubbles rise into the air. When a burning candle is brought near a gas- filled cleaner bubble, the gas present in the soap-bubble becks with a ‘pop’ sound. Only hydrogen gas burns fashioning a ‘pop’ sound. This shows that hydrogen gas is evolved in the process.
问题 5:在稀释酸时,为什么规定酸应该与水而不是水与酸结合?
回答:
When a concentrated acid is adjoined to water for prepping a dilute acid, also the heat is evolved gradationally and fluently soaked by the bulky quantum of water (to which the acid is being subjoined) still if water is added to concentrate.