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What is strong acid and weak acid?

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kumarvaibhav123 | Student, Grade 11 | Salutatorian

Posted September 25, 2011 at 4:02 AM via web

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What is strong acid and weak acid?

Tagged with acid and base, science

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element-water | Student | Salutatorian

Posted September 25, 2011 at 1:22 PM (Answer #1)

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A strong acid is an acid that is totally ionised in a solution. There aren't many strong acids in the world. Some examples of strong acids are sulphuric acids, hydrochloric acid, hydrobromic acid and nitric acid.

A weak acid is an acid that is only partially ionised in a solution. Anything that is not in the strong acid list is classified as a weak acid.

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jackmacc2000 | Student , Grade 11 | eNoter

Posted September 25, 2011 at 4:22 AM (Answer #2)

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A strong acid is an acid where the pH is lower than, generally, 3. These acids are in very high concentration of H+ ions (an acid of pH 3 has 0.001 moles per liter of H+), while a weak acid’s pH ranges from 3 to 7. These acids still have higher H+ concentration than OH-, however not a lot. Stronger acids tend to be more harmful to the human body than weak acids, so treat strong acids with caution!

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samhouston | Middle School Teacher | (Level 1) Associate Educator

Posted September 25, 2011 at 4:28 AM (Answer #3)

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The pH scale is used to measure how acidic or basic a substance is.  The scale goes from 0 to 14.  A substance with a pH of 0 through 6 is considered an acid, while a substance with a pH of 8 through 14 is considered a base.  A pH of 7 is neutral.  Uncontaminated, pure water is neutral.  The closer the number is to 7, the weaker the substance is.  The farther the number is from 7, the stronger the substance is. 

A substance with a pH of 1 or 2 would be a strong acid.  A substance with a pH of 5 or 6 would be a weak acid.

A substance with a pH of 13 or 15 would be a strong base.  A substance with a pH of 8 or 9 would be a weak base.

An example of a strong acid is vinegar.  The pH of vinegar is 2.4.  An example of a weak acid is citric acid.  The pH of citric acid is 4.8.

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phangsingsheen | Student , College Freshman | eNoter

Posted September 25, 2011 at 12:17 PM (Answer #4)

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strong acid are acid that dissociate completely when dissolve in water.the degree of dissciation is 1.

weak acid are acid that dissociate partially when dissolve in water..there will be H atom left in the acid and does not dissociate.

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