SAT2化学专题分析:Limiting Reagents.

2017-08-06 作者: 221阅读

  SAT2考试可以作为一个辅助性的参考,一定程度上增加学校对学生的了解,对录取也有一定的帮助。下面澳际小编搜集整理了SAT2化学专题分析:Limiting Reagents,希望能够帮助大家更好地备考SAT2物理考试。

  Have you ever noticed that hot dogs are sold in packages of 10, while the buns come in packages of eight? In this scenario, the buns are the limiting reactant in the sense that they limit the hot dog preparation to eight. The limiting reactant or reagent is the one that is consumed first in the chemical reaction, and its consumption halts the progress of the forward reaction.

  When answering questions about limiting reagents on the exam, your first step should always be to convert all the masses you were given into moles. You should set up your table as you did bore, only now you’ll have two amounts and thus two numbers of moles to get you started.

  Let’s look at a specific question, involving the Haber process. Basically, this is the process of making ammonia from the reaction of nitrogen and hydrogen gases. The reaction is shown below:

Molar mass (28.02) (2.02) (17.04)
Balanced equation N2 + 3H2 2NH3
No. of moles
Amount

  Suppose you have a total of 25.0 kg of nitrogen to react with a total of 5.00 kg of hydrogen. What mass of ammonia can be produced? Which reactant is the limiting reactant? What is the mass of the reactant that’s in excess? Insert the masses in the correct rows and find the number of moles of both.

Molar mass (28.02) (2.02) (17.04)
Balanced equation N2 + 3H2 2NH3
No. of moles 892 mol 2475 mol
Amount 25,000 g 5000 g

  Start with nitrogen. You have 892 moles of it available, and in order for the nitrogen to react completely with hydrogen, you’d need 3(892 mol) = 2676 moles of hydrogen, which you don’t have. Therore, hydrogen is the limiting reagent. Now let’s answer the other parts of the question. The mass of ammonia that can be produced is limited by the amount of hydrogen, so do your calculations based on the number of moles of hydrogen available. Your chart should look like the one below:

Molar mass (14.02) (2.02) (17.04)
Balanced equation N2 + 3H2 2NH3
No. of moles 825 mol used 2475 mol used therore 1650 mol produced
Amount 892 mol 23,117 g used 25,000g 5000 g 1650 mol (17.04) = 28,116 g produced

  以上便是澳际小编为大家整理的SAT2化学专题分析:Limiting Reagents的相关介绍,希望对大家有所帮助。更多SAT考试相关资料尽在澳际教育网SAT考试频道,澳际小编祝大家都能取得理想的SAT2化学考试成绩!

留学咨询

更多出国留学最新动态,敬请关注澳际教育手机端网站,并可拨打咨询热线:400-601-0022
  • 专家推荐
  • 成功案例
  • 博文推荐
  • 马育 向我咨询

    行业年龄 23年

    成功案例 7231人

    17年来为数千名学生打开通往新世界的大门,擅长名校申请和签证指导。专业的服务深受学生和家长们的认可。多次获得澳际集团 金牌服务奖杯

  • 高国强 向我咨询

    行业年龄 11年

    成功案例 2937人

    留学关乎到一个家庭的期望以及一个学生的未来,作为一名留学规划导师,我一直坚信最基本且最重要的品质是认真负责的态度。基于对学生和家长认真负责的原则,结合丰富的申请经验,更有效地帮助学生清晰未来发展方向,顺利进入理想院校。

  • 薛占秋 向我咨询

    行业年龄 10年

    成功案例 1869人

    从业3年来成功协助数百同学拿到英、美、加、澳等各国学习签证,递签成功率90%以上,大大超过同业平均水平。

  • Tara 向我咨询

    行业年龄 6年

    成功案例 1602人

  • 本科招生宣讲会|悉尼大学人文社科学院和理学院

    1671人阅读 查看原文

  • 成绩达不到澳八大要求?来这所世界排名前2%大学,商科就业率全澳第一!

    3774人阅读 查看原文

  • 重磅活动 | 澳国立2024中国信息日,欢迎报名!

    2296人阅读 查看原文

  • 澳洲首个本土大学排名出炉!几乎颠覆QS排名!全澳第一竟然是......

    1734人阅读 查看原文

我要查

澳际服务

我要读

热门国家申请