Quiz4 - Version 072/ABACA – Quiz 4 – Lyon –(53385 1...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Version 072/ABACA – Quiz 4 – Lyon – (53385) 1 This print-out should have 6 questions. Multiple-choice questions may continue on the next column or page – find all choices before answering. 1 2 3 4 5 6 7 AA AB AC AD BA BB BC 8 9 10 BACK NEXT BD CA CB CC CD 001 10.0 points A sample of an acid with an unknown con- centration was titrated with a known concen- tration of NaOH. However, before the NaOH was used in the titration, the NaOH was stan- dardized by titrating it with a solution con- taining a known mass of pure KHP. The rea- son the NaOH had to be standardized with the pure KHP is because the NaOH pellets used to make the NaOH solution were prob- ably impure and would be difficult to weigh accurately. 1. False 2. True correct Explanation: Most inorganic bases are solid metal hy- droxides, which react readily with CO 2 in the atmosphere and absorb water from the air. These properties make solid NaOH pellets impure and difficult to weigh out accurately. Primary standards, such as pure KHP, are used to standardize NaOH solutions in order to establish an accurate NaOH molarity for an acid-base titration. The reason that pri- mary standards, such as KHP, are not used to titrate unknown concentrations of acids or bases is because of cost. Pure primary standards are very expensive and many are difficult to prepare; therefore, they are used...
View Full Document

This note was uploaded on 10/21/2009 for the course CH 53395 taught by Professor Lyon during the Spring '09 term at University of Texas.

Page1 / 3

Quiz4 - Version 072/ABACA – Quiz 4 – Lyon –(53385 1...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online