Chemistry

Could you please give me a discriptive answer and explain what each term means? I have a hard time understanding chemistry. Thanx

q1
In a reaction between aqueous solutions of calcium chloride and sodium carbonate, a precipitate is formed. The experimental procedure which can be used to separate the solid from the solution is

A. titration
B. filtration
C. gas collection
D crystalization

q2.
Which technical procedure is similiar to the natural process which forms salt seposits?

A. titration
B. filtration
C. crystalization
D. fractional distillation

q3.
To determine the concentration of salt in ground water, the salt can be separated from the solution by

A. fractional distilling
B. filtering the solution
C. evaporating the solvent
D. lowering the temperture of the solution


Could you please give me a discriptive answer and explain what each term means? I have a hard time understanding chemistry. Thanx

q1
In a reaction between aqueous solutions of calcium chloride and sodium carbonate, a precipitate is formed. The experimental procedure which can be used to separate the solid from the solution is

A. titration
B. filtration
C. gas collection
D crystalization

Titration is when you have a known standard (such as 0.20 M HCl) and you use that, usually with an indicator, to determine the concentration of unknown solution. Usually a buret is used to add the titrant.
Filtration is a method to separate a solid phase from a liquid phase. For example, in the above example, CaCO3 is the precipitate (the solid) and you want to separate it from the liquid. The usual set up is to fold a piece of filter paper into fourths, place the folder paper into a 60 degree funnel, and pour the liquid and solid through. Gravity is what runs the system. It often takes quite some time, especially if the filter paper is not very porous. I don't know if you have been introduced to Buchner funnels or not but they are frequently used in organic chemistry to separate solids and liquids. They are much much larger than the small glass 60 degree funnels (often as much as 3-4 inches in diameter). A piece of filter paper is placed in the funnel (it has fairly large holes in the bottom (1/16 or 1/8 inch), the funnel is inserted into a flask, and the flask is connected to a water aspiration system so that a vacuum is pulled on the flask. That pulls the solvent through, usually quite quickly.
Gas collection usually entails allowing gas from a generator to flow into an inverted bottle of water. The gas displaces the water. You may remember collecting oxygen this way, or hydrogen gas, in freshman chemistry.
Crystallization is a way of purifying products that are made in some chemical reactions. It involves taking the product, a solid, and dissolving it in the minimum amount of some solvent at an elevated atemperature. Then the solution is allowed to cool and the solid will recrystallize in purer form if the right solvent was chosen.


q2.
Which technical procedure is similiar to the natural process which forms salt seposits?

A. titration
B. filtration
C. crystalization
D. fractional distillation

I have defined A, B, and C above. D of this part, fractional distillation, is performed by placing a mixture of liquids to be separated in a flask that can be heated. There is a side arm on the top part of the neck of the flask and a condenser is connected to the side arm. Finally, a thermometer is placed in the top of the flask (both to seal it off AND to allow us to know the temperature of the vapors). In practice, the flask is heated, vapors rise to the top, go through the open side arm, are condensed back to a liquid in the condenser, then drip out the bottom into a flask, beaker, or other container. The thermometer tells us the temperature at which that first product distilled. The temperature will stay at that point until all of "substance A" is distilled, then the temperature will rise until the next component vaporizes and goes through the same process. The mixture of liquids in the boiling pot is separated in this fashion into its "fractions" which is why it is called fractional distillation.

q3.
To determine the concentration of salt in ground water, the salt can be separated from the solution by

A. fractional distilling
B. filtering the solution
C. evaporating the solvent
D. lowering the temperture of the solution

I have defined A and B above.
C. evaporatiing the solvent is simple. We have a solution consisting of a solute (often a solid) dissolved in a solvent (usually a liquid). We let the solvent evaporate (just like water evaporates from a spill on the floor if we don't mop it up) and the solid is left behind in crystals.

D. Solutes are USUALLY more soluble in a solvent at elevated temperatures; therefore, lowering the temperature will often cause a solute to crystallize. This process actually is just a part of what was described in crystallization above.
I haven't given you the answers to any of these but just answered your question by giving definitions. Repost if there is something you don't understand.

  1. 👍 0
  2. 👎 0
  3. 👁 182

Respond to this Question

First Name

Your Response

Similar Questions

  1. Social Studies

    Question: Give an example of a topic for an informational essay that would allow you to use a definition strategy. Explain why your topic fits this organizational strategy. I'm not trying to get a full on answer, I just need help

  2. Algebra

    Write a recursive formula for the sequence 5, 18, 31, 44, 57, ... Then find the next term. I’m thinking that the answer is A. A. a1=-8; an=an-1+13. The next term is 70 B. a1=5; an=an-1+13. The next term is 70 C. a1=5;

  3. math

    The 3rd term of a geometric progression is nine times the first term.if the second term is one-twenty fourth the 5th term.find the 4th term. solution ar^2=9a r=sqr of 9 r=3.pls help me on how to get the first term(a)

  4. History

    2.)Which is the most likely reason George Washington refused a third term as president? A.)He felt a third term would give one man too much power. B.)He didn't think the citizens would support him for a third term. C.)He did not

  1. Math10

    The 4th term of an arithmetic sequence is 18 and the 6th term is 28. Give the first 3 terms. Use the formula

  2. Arithmetic Progression

    In an AP the 6th term is half the 4th term and the 3rd term is 15. a. Find the fist term and the common difference. b. How many times are needed to give a sum that is less than 65?

  3. algebra

    1)Find the 20th term of the arithmetic sequence in which a1=3 and d=7 a.143 b.136 c.140 d.133 an=a1+(n-1)d a20=3+(20-1)7 a20=3+(19)7 a20=3+133 answer=b 2)Write an equation for the nth term of the arithmetic sequence -3,3,9,15...

  4. Body Systems

    Please check my answers for the following questions. Thank you 1. Kinesi/o/logy, the combining form means? : A. bone B. development C. movement, motion x D. death 2. In the medical term necr/osis the root word means? A. ilium B.

  1. Math

    The fourth term of an arithmetic sequence is 18 and the sixth term is 28. Give the first 3 terms

  2. Maths

    The 4th term and the 19th term of an ap are -3 and 12 respectively. Find the common difference, 5th term and the number of terms which will give a sum of 135

  3. arithmetic

    first term and larst term of a geometric progression is 42.if the forth term is greater than the second term by 168, find the first term.the forth term.

  4. arithmetic

    1. The first and last term of an A.P are, a and l respectively, show that the sum of nth term from the beginning and nth term from the end is a + l. 2. If mth term of an A.P be 1/n and nth term be 1/m, then show that its mnth term

You can view more similar questions or ask a new question.