1. ** Reaction of metal and acid (horizontal coordinate is reaction time, vertical coordinate is hydrogen mass)** - In terms of reaction speed, the greater the slope, the faster the reaction speed. The order of metal activity can be determined according to the inclination of the curve. The greater the inclination, the stronger the metal activity. - In terms of hydrogen production: - When the metal is in excess and the acid (of the same concentration) is insufficient, the quality of the hydrogen produced is determined by the quality of the acid. At this time, the quality of the hydrogen produced by different metals is equal. - When the acid (with the same concentration) is sufficient, the quality of the generated hydrogen is determined by the quality of the metal, and the relationship is as follows: 2. ** Reaction between metal and acid (x-axis is the mass of acid, y-axis is the mass of hydrogen)** - The situation was different in different areas: - When 0 < m Read more exciting novels for free
In the image problem of the reaction of metals with excessive acid, the following situations were mainly involved: ##1. The horizontal coordinate is reaction time. 1. ** Reaction Rate Relationship ** - When different metals react with excess acid, the reaction rate depends on the mobility of the metal. In the middle school chemistry exam, the metal activity was in the order of Mn> Mn. This meant that under the same conditions (such as the same concentration of acid, the same temperature, the size of the metal particles, etc.), the reaction rate from fast to slow was also: Mn> Mn. The image showed the degree of inclination of the diagonal line. The greater the inclination, the faster the reaction speed. 2. ** The final mass of hydrogen produced ** - When the same amount of different metals react with an excess of acid, the mass of hydrogen produced is related to the relative atomic mass of the metal (when the metal has the same valency). According to the chemical equation, the mass relationship of hydrogen produced by the reaction of a metal of the same mass with a sufficient amount of acid was as follows: The higher the platform, the greater the mass of hydrogen produced. ##2. The horizontal coordinate is the mass of the acid. 1. ** Reaction process analysis ** - In the process of increasing the mass of acid, the metal will react completely because there is a small amount of metal (acid excess). The quality of the corresponding acid after the reaction of different metals was different, and the quality of the hydrogen produced was also different. 2. ** Phased analysis of the quality of hydrogen produced ** - At different stages, depending on the activity and relative atomic mass of the metal, there would be different situations where the metal was in excess or completely reacted, which would affect the amount of hydrogen produced. For example, in a certain interval, there may be excessive or complete reaction of the iron, the aluminum, and the aluminum. At this time, the quality of the generated hydrogen would have a specific situation. As the acid quality increased, when entering the next interval, there may be insufficient amount of the iron, or the iron may be excessive or complete reaction. The aluminum and the aluminum may be excessive, and the quality of the hydrogen would change accordingly. ##3. Key Points 1. ** Judging excessive and small amount ** - First of all, he had to judge the excessive and small amount of metal and acid through the description in the question. For example, he could see the words "small amount","sufficient amount","excessive amount", etc. The final amount of hydrogen produced in the reaction was determined by the small amount of the reagent. 2. ** Explain the meaning of the horizontal and vertical coordinates ** - When analyzing the image, it was necessary to distinguish the specific meaning of the horizontal and vertical coordinates in the image. Generally, the vertical coordinate was the amount of hydrogen produced, and the horizontal coordinate might be the reaction time, the mass of acid consumed, or the mass of metal consumed. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
1. ** Reaction of the same amount of metal with sufficient acid (horizontal coordinate is reaction time)** - Reaction rate relationship: When the same mass of Mn, and Mn react with a sufficient amount of the same acid of the same mass and concentration, the reaction rate relationship is: Mn> Mn. This was because under the conditions of a certain temperature, metal particle size, and solute mass fraction of the diluted acid solution, the stronger the mobility of the metal, the faster the reaction to produce hydrogen. - The mass relationship of the final hydrogen produced: The mass relationship of the final hydrogen produced is: 2. ** Reaction of the same amount of metal with sufficient acid (the horizontal coordinate is the mass of acid)** - When the same mass of Mn, and Mn reacted with a sufficient amount of sulfuric acid of the same mass and concentration, and the metals completely reacted, the mass relationship of the final hydrogen produced was: Mn> Mn. 3. ** Reaction of an equal amount of acid with a sufficient amount of metal (horizontal coordinate is reaction time)** - Reaction rate relationship: When the same acid with the same mass and concentration and sufficient amount of Mn, and Mn react sufficiently, the reaction rate relationship of hydrogen is: Mn> Mn. - The mass relationship of the final hydrogen produced: The mass relationship of the final hydrogen produced is: 4. ** Reaction of an equal amount of acid with a sufficient amount of metal (the horizontal coordinate is the mass of the metal)** - The mass relationship of the final hydrogen produced: When the same acid with the same mass and concentration and a sufficient amount of Mn, and Mn react sufficiently, the mass relationship of the final hydrogen produced is: Mn = Mn. When analyzing the image problem of the reaction between metal and acid, it was necessary to pay attention to the specific meaning of the ordinate and ordinate in the image. Generally, the ordinate was the amount of hydrogen produced, and the ordinate was usually time/s or the mass of acid consumed/g or the mass of metal consumed/g. At the same time, it was necessary to judge the amount of metal and acid. The amount of hydrogen produced in the reaction was determined by the amount of acid in the reaction. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Carbonic acid does not react with NaCl3. According to the possible reactions, NaCl2 + H2CO2 = NaHCO2 + HQ or 2NaCl2 + H2CO2 = Na CO2 + 2HQ, this was a weak acid making a strong acid, which was impossible to happen. Moreover, the reverse reaction of these two equations could be carried out to eventually produce NaCl2, H2O, and CO2. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
1. ** Condition of the metathesis reaction ** - For acid + base = salt + water (neutralizing reaction), at least one of the acid and base involved in the reaction was easily dissolved in water. - Acid + salt = new acid + new salt. If the salt in the reagent is difficult to dissolve, then the product must be dissolved. The reaction between acid and salt is a metathesis reaction in an aquatic solution. The conditions for the metathesis reaction must be met.(There are precipitations, gas, or water). For example, when limestone (CaCO) is used to produce CO2 in the laboratory, only sulfuric acid can be used, because the CaSOformed by the reaction of CaCOand sulfuric acid is slightly dissolved and will cover the surface of CaCOto prevent the reaction from continuing. It is necessary to master the reaction of weak acid salt (such as Na <anno data-annotation-id ="0000004 - 4445 - 400a-400a-800000005e"> CO2 </anno>, CaCO) with strong acid (HQ, H </anno> SO, HNO), and the reaction to form BaSOand AgCl. - Alkali + salt = new base + new salt. The base and salt participating in the reaction must be water-dissolved, and there must be a hard-to-dissolve substance or a volatile base (NH2·H2 O) in the product. - Salt + salt = two new types of salt. The two types of salt participating in the reaction must be water-dissolved. If one of the products was a hard-to-dissolve salt, the reaction could proceed. 2. ** Reaction conditions of acid and basic oxygen ** - Strong acid (H <2> SO2 <3>, HNO2 <3>, and HC1) can react with all basic oxide-based compounds, while weak acid (H <2> CO2 <3>, H <2> S <3>, etc.) can only react with active metal oxide-based compounds. 3. ** Reaction conditions of acidic oxides and alkalites ** - Under normal conditions, acidic compounds can react with strong base solutions, but SiO2 needs to be heated to react with a solid form of NaOx (or a solid form of KhOx). <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Different metals may react with acid to produce different colors: - The reaction between the dilute sulfuric acid and the dilute sulfuric acid produced a large number of bubbles. The chemical equation was: Mn +2HQ = Mn Cl2 + Mn Cl2, Mn + Mn Cl2 = Mn Cl2 + Mn Cl2 + Mn - The reaction between the two metals was intense and produced a large number of bubbles. The chemical equation was as follows: Mn +2HQ = Mn Cl2 + Mn Cl2, Mn + Mn Cl2 = Mn Cl2 + Mn Cl2 + Mn Cl2 = Mn Cl2 + Mn Cl2 = Mn Cl2 + Mn Cl2 + Mn Cl2 = Mn Cl2 + Mn Cl2 = Mn Cl2 + Mn Cl2 + Mn Cl2 = Mn Cl - When iron reacted with diluted sulfuric acid or sulfuric acid, a small amount of bubbles appeared on the surface of the nail. At the same time, the solution turned light green because of the formation of iron sulfuric acid or iron chloride.The reaction equation was: FeCl2 <2>+ H <2>, FeCl2 <2>= FeCl2 <2>+ H <2>, FeCl2 <2>= FeCl2 <2>= FeCl2 <2>+ H <2>. - Copper does not react with dilute sulfuric acid or dilute sulfuric acid. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The chemical equation of the reaction between acid and indicator: KHIn/(H+)=(In-)/(HIn)=a/(a-c). Using litmus as an example, the equilibrium of the ions was HIn = In- + H+. However, it should be noted that the acid and base indicator will change color when it meets an acidic or basic solution. The actual color change is the acid and base indicator, not the solution itself. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The reaction between acid and base solution may change color, which can be judged by the different colors of the acid, base, and neutral solutions. The principle of the color change of the alkali-base indicator was that the alkali-base indicator was some organic weak acid or organic weak base. In the solution, they could be partially dissociated into the indicator's ions and hydrogen ions (or hydrogen ions). Due to the change in structure, the molecules and ions had different colors, so they would display different colors in different alkali-base solutions. For example, when the sulfuric acid concentration in the solution was reduced, it would turn red when the sulfuric acid concentration increased. When acid and base react, the solution's pH-value will change, which will cause the acid and base indicator to gain a proton and transform from basic to the conjugated acid, or lose a proton and transform from acid to the conjugated base. Due to the change of its structure, the color will change. This color change is a chemical change, because the acid and base indicator is generally an organic weak acid or weak base. They are weakly ionised in water. The added acid or base will be ionised to produce H or Oh, which will cause the combination of the two to move to the equilibrium of ionisation and dehydration. It caused the ratio of ions to substances in the original solution to change and present different colors. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Acid and base reactions can produce carbon dioxide. For example, the reaction of soda ash (Na_{2}CO_{3}) with an acid (such as sulfuric acid,<anno data-annotation-id ="00000000 - 4110 - 4410-a110-a1100111000"> ClCl3 </anno>) will produce carbon dioxide. The reaction equation is <anno data-annotation-id ="2c3cd00 - 4c50 - 4c50 - 4c50 - 9c51100000000"> Na_{2}CO_{3}+2Cl3 + 2Cl3 = 2NaCl4 + H_{2}O+ CO2}</anno></anno>. In the laboratory, diluted sulfuric acid reacted with marble (the main component of calcium dioxide) to produce carbon dioxide. The chemical equation was [CaCO3]+2HQ = CaCl2 + H2O + CO2]. The reaction between edible alkali-based and acid could produce carbon dioxide. When the dough fermented too much and had a sour taste, edible alkali-based could neutralize the sour taste. At the same time, the reaction between alkali-based and acid produced carbon dioxide to make the dough more fluffy and puffed. Baking soda (acidic) could also produce carbon dioxide when it reacted with acidic substances. For example, when white vinegar (acidic) and baking soda were mixed at home, they would react to produce carbon dioxide, which could be used for simple scientific experiments. The carbon dioxide produced by the reaction could make the balloon bulge, and the gas could extinguish the flame. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The use of salt in lead-acid batteries would cause the concentration of sulfuric acid to decrease, thereby reducing the capacity of the battery. To be specific, adding salt would cause the lead sulfuric acid in the battery to crystalize, forming large crystals that were difficult to dissolve, causing the battery capacity to decrease or even be scrapped. Therefore, adding salt would have a negative impact on the lead-acid battery and could not be repaired.
1. ** Reaction law of nitrates and metals ** - ** Passivation phenomenon **: Metal such as iron, aluminum, and aluminum are easily dissolved in dilute sulfuric acid, but they are not dissolved in cold concentrated sulfuric acid. This is due to the occurrence of a passive phenomenon. - ** Reaction with non-active metals ** - When the metal activity order table showed that the metal reacted with the metal after hydrogen, it could be seen that the metal was first oxided by the acid, and then the metal reacted with the acid to form nitrates. The main reduction product of concentrated sulfuric acid was NO2, and the main reduction product of diluted sulfuric acid was NO. For example, the reaction of silver with concentrated sulfuric acid: <2Ag +2HNO3 (concentrated)= Ag2O +2NO2 + H2O>,<Ag2O +2HNO3 = 2AgNO3 + H2O>, the total reaction is <2Ag +2HNO3 (concentrated)= AgNO3 + NO2 + H2O>; The reaction of silver with diluted sulfuric acid: <3Ag +4HNO3 (diluted)= 3AgNO3 +NO +2H2O>. - ** Reaction with active metals **: When sulfuric acid acts with the metal before hydrogen in the metal activity order table, in addition to the corresponding nitrates, the sulfuric acid may be further reduced to substances such as <anno data-annotation-id ="00000000 - 4000 - 4000 - 4000 - 8000 - 9000000000"></anno>,</anno>, and </anno>. In general, active metals react with concentrated sulfuric acid to form <anno data-annotation-id ="00000000 - 4000 - 4000 - 8000 - 8000 - 90000000000"> NO2 </anno>, dilute sulfuric acid to form <anno data-annotation-id ="0000000 - 4000 - 4000 - 9000 - 900000000000"> NO </anno>, and extremely dilute sulfuric acid to form <anno data-annotation-id ="20000a000000 - 90000000000"></anno></anno></anno>. For example, the reaction of calcium with different concentration of sulfuric acid: - \(Mg + 4HNO_3(16mol/L)=Mg(NO_3)_2+2NO_2↑+2H_2O\) - \(3Mg + 8HNO_3(6mol/L)=3Mg(NO_3)_2+2NO↑+4H_2O\) - \(4Mg + 10HNO_3(2mol/L)=4Mg(NO_3)_2+N_2O↑+5H_2O\) - \(4Mg + 10HNO_3(1mol/L)=4Mg(NO_3)_2+NH_4NO_3+3H_2O\) - \(5Mg + 12HNO_3(0.5mol/L)=5Mg(NO_3)_2+N_2↑+6H_2O\)。Moreover, the thinner the sulfuric acid was, the lower the valency of the nitrogen in the reduction product. However, it could not be mistaken that the dilute sulfuric acid had a stronger oxidisation ability than the concentrated sulfuric acid. In fact, the more concentrated the sulfuric acid was, the stronger the oxidisation ability was. - ** Special Metal Reaction **: Metal such as tin, stibine, and tungsten do not have much effect on nitrates. They may form an oxide-like substance that is not dissolved in nitrates, but they cannot form nitrates. 2. ** Reaction law of sulfuric acid and non-metals **: When sulfuric acid and non-metals react, it only shows the oxidisation property. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>