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LARN 125 C32D1

Start the following in class:

1.a. The first required focus topic, J125A, for today is

What are the meanings of the terms

  1. coarse mixture,
  2. suspension,
  3. colloid, and
  4. solution ?

1.b. The second required focus topic, J125B for today is

Copy the following chart and fill in examples for the different types of mixtures.  Coarse mixture

Suspension Colloid Solution
Scatters Light from a Beam of Light [Exhibits the Tyndall Effect]? [Yes or No]
Typical Appearance of the Mixture
Typical Size Range of Suspended or Dissolved Particles
Generally Separable by Letting it Settle for a Time (Sedimentation)? [Yes or No]
Appearance [Variegated, Non-Uniform, Cloudy, Clear?]
Degree of Uniformity Descriptor [Heterogeneous orHomogeneous?]
Approximate Sizes of Dispersed Particles               > ____nm   ____nm – ____nm           <  ____nm
Separable by Ordinary Filters?  [Yes or No]
Exhibits Brownian Motion? [Yes or No]
Example #1:
Example #2:

2.  Do all the pages in the chapter 15 Water and Aqueous Systems [Formative] Test as a formative assessment to find out some of the things that you do and do not know, and not as a research project.

  • If you did not obtain a formative test packet for the chapter in class, go to MNSD Google Drive > Student Resources > Formative Tests and print off a copy of the test for the chapter you are studying.  Each chapter test is identified by a name whose last two digits is the chapter number.  For example, the chcta16.pdf designates the chemistry chapter 16 test “A”.  When the chapter formative test is opened, the first page will have the words “Chapter Test A” in the title.
  • For each question or problem challenge for which a work space is given, either answer the question to the best of your ability using one or more full sentences, or answer the problem to the best of your ability by recording the numbers and units of measure of what is sought for, of what was given, and of what, if any, conversion or comparison ratios could be used to obtain a correct solution.  Circle or box your final result after expressing your result to the proper number of significant figures, followed by the proper unit of measure.
  • This is an important assignment. Each formative test is a real chapter test that some teachers in other schools might use as a chapter test, so after taking the test, make sure that you understand each unfamiliar word, idea, concept, and problem.  Be sure to finish this packet in its entirety.

After doing the formative assessment, but before you demonstrate your understanding on our class’ chapter summative assessment, you will check all your responses using green ink check marks √ for each correct response, and by lining out (striking through) and inserting improved text in green ink when you think the suggested response expresses your present understanding in a better way.   While doing that, make sure that you understand each idea that you originally did not have a complete understanding of.  Then you will be able to study more efficiently by studying that which you corrected in green ink.

Recommended for those who have time left in their 45 minute study period, but not required of all:

1.   For today’s third journal entry, J125C, on your three holed 8.5 inch by 11 inch ruled paper, you are to construct a concept map.  Please turn to page 464 in your text and, in your learning journal, construct a concept map relating the six terms listed at the bottom of the page.  Connect related terms with arrows such that the subject of each sentence explaining the relationship is at the tail of the arrow, the verb describing the relationship of the subject to the predicate is written beside the arrow, and the arrow head is touching the oval of the term which is the object or predicate nominative of the verb that you have chosen.

2. Think about the fifteen properties of covalent molecular substances listed on the Properties to be understood worksheet describing differences in the properties of metals, ionic compounds, covalent network solids, and covalent molecular compounds.  Continue to study this handout for understanding and review how the typical properties of members of these classes of compounds depend on whether the compound has localized or delocalized electrons, and upon whether strong metallic, ionic, or covalent bonding or weak van der Waals forces of attraction are predominant between representative particles of the substances.  Try to understand how each property of a given covalent molecular substance is related to the groups of covalently bonded atoms that form molecules whose van der Waals attractive forces only weakly attract other molecules.

3. How do the properties of covalent molecular substances with hydrogen bonding typically differ from those covalent molecular substances that form molecules whose van der Waals attractive forces only weakly attract other molecules?

4.  Why do solvents and solutes of similar polarity (“likes”) tend to dissolve in each other, but solvents and solutes of dissimilar polarities (“unlikes”) not tend to dissolve in each other?

For a more advanced explanation of this, watch the video at this link: https://www.youtube.com/watch?v=M4iqSTAr0pk