/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 145 When preparing a solution of kno... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 4: Problem 145

When preparing a solution of known concentration, explain why one must first dissolve the solid completely before adding enough solvent to fill the volumetric flask to the mark.

Short Answer

Expert verified
Complete dissolution ensures uniform solute distribution; filling to the mark achieves precise concentration.

Step by step solution

01

Understanding the Problem

To prepare a solution of a known concentration, it means you need to dissolve a specific amount of solid chemical (solute) in a solvent to reach a precise concentration.
02

Importance of Full Dissolution

First, ensure the solid solute is completely dissolved in a portion of the solvent. This ensures that the solute is evenly distributed throughout the solution, which is critical for achieving the correct concentration.
03

Solvent Addition and Final Adjustment

After the solute has completely dissolved, add more solvent, gradually filling the volumetric flask to the calibration mark. This mark indicates the desired total volume of the solution.
04

Ensuring Accurate Concentration

The complete dissolution of the solute before reaching the final volume ensures that no solid particles remain undissolved, which would otherwise lower the actual concentration of the solution. Adjusting to the marked volume afterward ensures the concentration is accurate as calculated.

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.

Over 30 million students worldwide already upgrade their learning with 91影视!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Solute Dissolution
When preparing a solution, the first critical step is the dissolution of the solute in a solvent. This means the solid substance, or solute, must be fully dissolved into the liquid to ensure an even distribution.
  • Start by adding a small, measureable portion of solvent to the solute.
  • Stir the mixture thoroughly to make sure all solute particles dissolve.
Once the solute is fully dissolved, you avoid uneven concentration throughout the solution. Any remaining particles indicate incomplete dissolution and can affect the accuracy of your calculations.
Volumetric Flask Use
A volumetric flask is an essential piece of laboratory glassware. It's specifically designed to hold a precise volume of liquid.
  • The flask is marked with a line on its neck to indicate the total volume it can hold.
  • Its shape helps ensure that solutions are well mixed.
Using a volumetric flask ensures that when you fill to the line, you can trust that you have the exact volume needed for your concentration calculations.
Concentration Accuracy
Achieving accurate concentration is all about precision in mixing and measuring.
  • Begin by fully dissolving the solute before making up the solution to final volume. This avoids errors in concentration.
  • Make sure to adjust the volume level to the calibration mark on the volumetric flask for accuracy.
Any deviation from these steps could result in incorrect concentrations, which would affect experimental outcomes, possibly leading to errors if concentrations are used in further reactions or computations.
Solvent Addition
After ensuring that all the solute is dissolved, the next step is careful addition of more solvent until the solution reaches the mark on the volumetric flask.
  • This process is critical for maintaining the desired concentration.
  • Always add the solvent gradually. Rapid addition can make it easy to overshoot the mark, leading to dilution issues.
Filling the flask carefully to the mark ensures that the final volume contains the correct amount of solute, based on the specific concentration needed for the experiment or process.

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

You have \(505 \mathrm{~mL}\) of a \(0.125 \mathrm{M} \mathrm{HCl}\) solution and you want to dilute it to exactly \(0.100 \mathrm{M}\). How much water should you add?

Phosphorus forms many oxoacids. Indicate the oxidation number of phosphorus in each of the following acids: (a) \(\mathrm{HPO}_{3},\) (b) \(\mathrm{H}_{3} \mathrm{PO}_{2},\) (c) \(\mathrm{H}_{3} \mathrm{PO}_{3}\), (d) \(\mathrm{H}_{3} \mathrm{PO}_{4},\) (e) \(\mathrm{H}_{4} \mathrm{P}_{2} \mathrm{O}_{7}\) (f) \(\mathrm{H}_{5} \mathrm{P}_{3} \mathrm{O}_{10}\)

Give a chemical explanation for each of the following: (a) When calcium metal is added to a sulfuric acid solution, hydrogen gas is generated. After a few minutes, the reaction slows down and eventually stops even though none of the reactants is used up. Explain. (b) In the activity series, aluminum is above hydrogen, yet the metal appears to be unreactive toward hydrochloric acid. Why? (Hint: Al forms an oxide, \(\mathrm{Al}_{2} \mathrm{O}_{3},\) on the surface.) (c) Sodium and potassium lie above copper in the activity series. Explain why \(\mathrm{Cu}^{2+}\) ions in a \(\mathrm{CuSO}_{4}\) solution are not converted to metallic copper upon the addition of these metals. (d) A metal M reacts slowly with steam. There is no visible change when it is placed in a pale green iron(II) sulfate solution. Where should we place \(\mathrm{M}\) in the activity series? (e) Before aluminum metal was obtained by electrolysis, it was produced by reducing its chloride \(\left(\mathrm{AlCl}_{3}\right)\) with an active metal. What metals would you use to produce aluminum in that way?

Arrange the following species in order of increasing oxidation number of the sulfur atom: (a) \(\mathrm{H}_{2} \mathrm{~S},(\mathrm{~b}) \mathrm{S}_{8}\) (c) \(\mathrm{H}_{2} \mathrm{SO}_{4}\) (d) \(\mathrm{S}^{2-}\) (e) HS \(^{-}\), (f) \(\mathrm{SO}_{2},(\mathrm{~g}) \mathrm{SO}_{3}\)

Chlorine forms a number of oxides with the following oxidation numbers: \(+1,+3,+4,+6,\) and \(+7 .\) Write a formula for each of these compounds.
See all solutions

Recommended explanations on Chemistry Textbooks

Chemistry Branches

Read Explanation

Inorganic Chemistry

Read Explanation

Making Measurements

Read Explanation

Organic Chemistry

Read Explanation

Kinetics

Read Explanation

Ionic and Molecular Compounds

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.