Login Registrieren

Warning: foreach() argument must be of type array|object, bool given in /var/www/html/web/app/themes/studypress-core-theme/template-parts/header/mobile-offcanvas.php on line 20

Chapter 27: Q4P (page 767)

What measures can be taken to decrease the relative supersaturation during a precipitation?

Short Answer

Expert verified

The measures to be taken to decrease the relative supersaturation during a precipitation

Slow addition
Homogenous solution
Dilute reagents
Increased temperature

Step by step solution

01

Definition

It is an analytical technique that uses a precipitation reaction to separate ions from a solution. The chemical that is added to cause the precipitation is called the precipitant or precipitating agent

02

Measures to be taken to decrease the Supersaturation

1. Slow addition of precipitating agent and mixing during addition

2. Precipitate forms homogenous solution – precipitating agent in this case is synthesized in the solution and isn’t added mechanically.

3. Precipitating using dilute reagents

4. Increased temperature – solubility is increased.

Unlock Step-by-Step Solutions & Ace Your Exams!

Full Textbook Solutions
Get detailed explanations and key concepts
Unlimited Al creation
Al flashcards, explanations, exams and more...
Ads-free access
To over 500 millions flashcards
Money-back guarantee
We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

${LaCoO}_{3 + x}$ , has a perovskite structure (Box 19-1) with variable oxygen content. The figure shows the thermogravimetric curve observed when 41.8724m gwere heated in role="math" localid="1665035505591" $5 vol % H_{2} in Ar . La (II)$ does not react, but cobalt is reduced to Co(s)

(a) What is the oxidation state of cobalt in the ideal formula ${LaCoO}_{3}$

(b) Write the reaction of role="math" localid="1665035588740" ${LaCoO}_{3} with H_{2}$ to produce ${La}_{2} O_{3} with (s), Co (s), and H_{2} O (s)$

(c) If $41.8724 mg of {LaCoO}_{3}$ react completely, what will be the mass of product $({La}_{2} O_{3} + (Co)$ ?

(d) Write the balanced reaction of role="math" localid="1665035782894" ${LaCoO}_{3 + x} with H_{2} O$ to produce ${La}_{2} O_{3}, Co, and H_{2} O . If 41.8724 mg of {LaCoO}_{3 + 1}$ react completely; what will be the mass of solid product? Your answer will be an expression with x in it.

(e) From the observed product mass $(37.767 mg) at 700 ° c$ , find x in ${LaCoO}_{3 + x}$ Write the formula of the starting solid.

(f) In part (c), the mass lost from the ideal formula ${LaCoO}_{3 + x}$ , is 4.0877 mg. What is the product nearrole="math" localid="1665035980286" $500 ° C$ where the mass is -40.51 mg?

Statistics of coprecipitation. 17In Experiment 1,200.0mL of solution containing 10.0mg of ${SO}_{4}^{2 -}$ (from ${Na}_{2} {SO}_{4}$ ) were treated with excess ${Bacl}_{2}$ solution to precipitate ${BaSO}_{4}$ containing some coprecipitated ${Cl}^{-}$ . To find out how much coprecipitated was present, the precipitate was dissolved in 35mL of 98wt% $H_{2} {SO}_{4}$ and boiled to liberate , which was removed by bubbling gas through the $H_{2} {SO}_{4}$ . The HCI/ $N_{2}$ stream was passed into a reagent solution that reacted with to give a color that was measured. Ten replicate trials gave values of 7.8,9.8,7.8,7.8,7.8,7.8,13,7,12.7,13.7, and 12.7. Experiment 2 was identical to the first one, except that the mL solution also contained of from ). Ten replicate trials gave 7.8,10,8,8.8,7.8,6.9, 8.8, 15.7 , 12.7 , 13.7and $14.7 {μmolCl}^{-}$ .

(a) Find the mean, standard deviation, and 95% confidence interval for ${Cl}^{-}$ in each experiment.

(b) Is there a significant difference between the two experiments? What does your answer mean?

(c) If there were no coprecipitate, what mass of ${BaSO}_{4}$ (FM 233.39) would be expected?

(d) If the coprecipitate is (FM 208.23), what is the average mass of precipitate $({BaSO}_{4} + {BaCl}_{2})$ in Experiment 1. By what percentage is the mass greater than the mass in part (c)?

Consider a mixture of the two solids,

${BaCl}_{2} 2 H_{2} O (FM 244.26) and KCI (FM 74.551)$ , in an unknown ratio. (The notation ${BaCl}_{2} 2 H_{2} O$ means that a crystal is formed with two water molecules for each ${BaCl}_{2}$ ) When the unknown is heated to $160 ° C$ for 1h, the water of crystallization is driven off:

${BaCl}_{2} 2 H_{2} O (s) \overset{160 °}{\to} BaCI (s) + 2 H_{2} O (g)$

A sample originally weighing 1.7839 g weighed 1.5623 g after heating. Calculate the weight percent Ba,K and Cl ofin the original sample.

Why are many ionic precipitates washed with electrolyte solution instead of pure water?

A 1.000-g sample of unknown gave 2.500 g of bis (dimethylglyoximate)nickel (II) (FM 288.91) when analyzed by Reaction 27-7. Find the weight percent of Ni in the unknown.

See all solutions

Recommended explanations on Chemistry Textbooks

Ionic and Molecular Compounds

Read Explanation

Organic Chemistry

Read Explanation

Nuclear Chemistry

Read Explanation

Making Measurements

Read Explanation

The Earths Atmosphere

Read Explanation

Kinetics

Read Explanation

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free