All Courses
Explore Courses UPSC Exam UPSC Test Series Free Notes EduRev Infinity Get the App Login Join for Free
Sign in Open App
ACT Exam  >  ACT Questions  >  Which of the following is not a Lewis acid?a)... Start Learning for Free
Which of the following is not a Lewis acid?
  • a)
    aluminium chloride
  • b)
    sodium ion
  • c)
    sulphur tetrafluoride
  • d)
    hydroxide ion
Correct answer is option 'D'. Can you explain this answer?
Clear all your ACT doubts with EduRev
Most Upvoted Answer
Which of the following is not a Lewis acid?a)aluminium chlorideb)sodiu...
Lewis acids are molecules with an incomplete octet of central atoms like aluminium chloride, simple cations like sodium ion, and molecules in which the central atom has vacant d-orbital like sulphur tetrafluoride, but hydroxide ion is a negatively charged species. So it is not a Lewis acid.
Free Test
FREE
Start Free Test
Start Free Test
Community Answer
Which of the following is not a Lewis acid?a)aluminium chlorideb)sodiu...
Explanation:

In order to determine which of the given options is not a Lewis acid, we need to understand what a Lewis acid is.

Definition: A Lewis acid is a chemical species that can accept an electron pair from a Lewis base to form a coordinate covalent bond.

Explanation of each option:

a) Aluminium chloride: Aluminium chloride (AlCl3) is a Lewis acid. It has an empty p-orbital in its central aluminium atom which can accept an electron pair from a Lewis base.

b) Sodium ion: Sodium ion (Na+) is not a Lewis acid. It is a cation with a positive charge, but it does not have any vacant orbital to accept an electron pair from a Lewis base.

c) Sulphur tetrafluoride: Sulphur tetrafluoride (SF4) is a Lewis acid. It has an empty d-orbital in its central sulphur atom which can accept an electron pair from a Lewis base.

d) Hydroxide ion: The hydroxide ion (OH-) is not a Lewis acid. It is a negatively charged anion with a lone pair of electrons. It acts as a Lewis base by donating its lone pair of electrons to form a coordinate covalent bond with a Lewis acid.

Conclusion:

The correct answer is option 'D' - hydroxide ion. It is not a Lewis acid because it acts as a Lewis base by donating its lone pair of electrons.
Explore Courses for ACT exam

Similar ACT Doubts

In its refined form, iron is a shiny, silver-gray metal; however, when refined iron is exposed to atmospheric conditions for an extended period of time, its surface becomes flaky, pitted, and red- or orange-colored. This process is known as "rusting," and the new flaky, orange or red substance is called "rust."Below, two scientists discuss how rust forms and the composition of rust.Scientist 1:Both water and oxygen are needed for rust to form. Water is an electrolyte, meaning that it allows ions to move within it. When iron comes into contact with water, some iron naturally dissociates into iron ions (Fe2+) and free electrons. Additionally, when atmospheric oxygen (O2) dissolves in water, some oxygen reacts with water to form hydroxide ions (OH-). Because water allows ions to move freely, iron ions and hydroxide ions combine to form a new compound: iron hydroxide. However, iron hydroxide is not a stable compound. Over time, as water evaporates, it changes into a hydrated form of iron oxide. This is rust.Salts can act as catalysts for rust formation, meaning that they speed up the rate at which rust forms. However, rust can form in pure water, in the absence of added salts.Increasing the ambient temperature increases the rate of rust formation. Additionally, increasing the amount of irons surface area that is exposed to water also increases the rate at which rust forms. However, because a layer of rust is porous to water and oxygen, water and oxygen will continue to cause the interior of a piece of iron to rust even after the irons surface has been rusted.Scientist 2:Attack by acids causes rust to form. In water, acids ionize to create positively-charged hydronium (H+) ions and negatively-charged anions. Hydronium ions are electron-deficient; because of this, they attract electrons from iron. This creates iron ions (Fe2+), which are soluble in water. Once dissolved in water, iron ions react with dissolved atmospheric oxygen (O2) to create iron oxide, or rust.Acids can come from a variety of sources. For example, when carbon dioxide in the atmosphere dissolves in water, carbonic acid (H2CO3) is created. Carbonic acid is the most common cause of rusting. However, other environmental sources of acids exist. Rainwater is normally slightly acidic because it has come into contact with molecules in the atmosphere, like sulfur dioxide and nitrogen oxides. These molecules also dissolve in water to form acids. Additionally, iron itself may contain impurities such as phosphorous and sulfur, which react with water to produce acids. Both acidic environments and impurities within iron itself create the conditions under which iron rusts.Rusting can be prevented by painting the surface of iron, thus preventing it from coming into contact with water, oxygen, and acids. Iron can also be protected in a process called "galvanizing," which involves coating iron in a thin layer of zinc. Because zinc is more reactive than iron, it is corroded while the iron is protected.Q. Given that all of the following are true, which of the following, if found, provides the strongest evidence against Scientist 1s hypothesis?

In its refined form, iron is a shiny, silver-gray metal; however, when refined iron is exposed to atmospheric conditions for an extended period of time, its surface becomes flaky, pitted, and red- or orange-colored. This process is known as "rusting," and the new flaky, orange or red substance is called "rust."Below, two scientists discuss how rust forms and the composition of rust.Scientist 1:Both water and oxygen are needed for rust to form. Water is an electrolyte, meaning that it allows ions to move within it. When iron comes into contact with water, some iron naturally dissociates into iron ions (Fe2+) and free electrons. Additionally, when atmospheric oxygen (O2) dissolves in water, some oxygen reacts with water to form hydroxide ions (OH-). Because water allows ions to move freely, iron ions and hydroxide ions combine to form a new compound: iron hydroxide. However, iron hydroxide is not a stable compound. Over time, as water evaporates, it changes into a hydrated form of iron oxide. This is rust.Salts can act as catalysts for rust formation, meaning that they speed up the rate at which rust forms. However, rust can form in pure water, in the absence of added salts.Increasing the ambient temperature increases the rate of rust formation. Additionally, increasing the amount of irons surface area that is exposed to water also increases the rate at which rust forms. However, because a layer of rust is porous to water and oxygen, water and oxygen will continue to cause the interior of a piece of iron to rust even after the irons surface has been rusted.Scientist 2:Attack by acids causes rust to form. In water, acids ionize to create positively-charged hydronium (H+) ions and negatively-charged anions. Hydronium ions are electron-deficient; because of this, they attract electrons from iron. This creates iron ions (Fe2+), which are soluble in water. Once dissolved in water, iron ions react with dissolved atmospheric oxygen (O2) to create iron oxide, or rust.Acids can come from a variety of sources. For example, when carbon dioxide in the atmosphere dissolves in water, carbonic acid (H2CO3) is created. Carbonic acid is the most common cause of rusting. However, other environmental sources of acids exist. Rainwater is normally slightly acidic because it has come into contact with molecules in the atmosphere, like sulfur dioxide and nitrogen oxides. These molecules also dissolve in water to form acids. Additionally, iron itself may contain impurities such as phosphorous and sulfur, which react with water to produce acids. Both acidic environments and impurities within iron itself create the conditions under which iron rusts.Rusting can be prevented by painting the surface of iron, thus preventing it from coming into contact with water, oxygen, and acids. Iron can also be protected in a process called "galvanizing," which involves coating iron in a thin layer of zinc. Because zinc is more reactive than iron, it is corroded while the iron is protected.Q. Lye (sodium hydroxid e) is a base that neutralizes acids. Suppose that lye is added to water in which an iron pipe has been immersed. According to Scientist 2, the pipes rate of rusting will most likely __________.

Top Courses for ACTView all

Top Courses for ACT

Which of the following is not a Lewis acid?a)aluminium chlorideb)sodium ionc)sulphur tetrafluorided)hydroxide ionCorrect answer is option 'D'. Can you explain this answer?
Question Description
Which of the following is not a Lewis acid?a)aluminium chlorideb)sodium ionc)sulphur tetrafluorided)hydroxide ionCorrect answer is option 'D'. Can you explain this answer? for ACT 2025 is part of ACT preparation. The Question and answers have been prepared according to the ACT exam syllabus. Information about Which of the following is not a Lewis acid?a)aluminium chlorideb)sodium ionc)sulphur tetrafluorided)hydroxide ionCorrect answer is option 'D'. Can you explain this answer? covers all topics & solutions for ACT 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Which of the following is not a Lewis acid?a)aluminium chlorideb)sodium ionc)sulphur tetrafluorided)hydroxide ionCorrect answer is option 'D'. Can you explain this answer?.
Solutions for Which of the following is not a Lewis acid?a)aluminium chlorideb)sodium ionc)sulphur tetrafluorided)hydroxide ionCorrect answer is option 'D'. Can you explain this answer? in English & in Hindi are available as part of our courses for ACT. Download more important topics, notes, lectures and mock test series for ACT Exam by signing up for free.
Here you can find the meaning of Which of the following is not a Lewis acid?a)aluminium chlorideb)sodium ionc)sulphur tetrafluorided)hydroxide ionCorrect answer is option 'D'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of Which of the following is not a Lewis acid?a)aluminium chlorideb)sodium ionc)sulphur tetrafluorided)hydroxide ionCorrect answer is option 'D'. Can you explain this answer?, a detailed solution for Which of the following is not a Lewis acid?a)aluminium chlorideb)sodium ionc)sulphur tetrafluorided)hydroxide ionCorrect answer is option 'D'. Can you explain this answer? has been provided alongside types of Which of the following is not a Lewis acid?a)aluminium chlorideb)sodium ionc)sulphur tetrafluorided)hydroxide ionCorrect answer is option 'D'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice Which of the following is not a Lewis acid?a)aluminium chlorideb)sodium ionc)sulphur tetrafluorided)hydroxide ionCorrect answer is option 'D'. Can you explain this answer? tests, examples and also practice ACT tests.
Explore Courses for ACT exam

Top Courses for ACT

Explore Courses
SaveJoin the Discussion on the App for FREE
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev
Get App
© EduRev
Education Revolution
Signup to see your scores go up within 7 days!
Access 1000+ FREE Docs, Videos and Tests
Takes less than 10 seconds to signup