How Can We Know if Chemicals React?

  • Thread starter Stratosphere
  • Start date
In summary, it is possible to know what chemicals react with other chemicals through means other than experimentation, such as predicting based on substance structure. However, experimentation is the only way to be 100% certain. The provided example also demonstrates that while caffeine is soluble in water and chloroform, tannin forms a salt that is insoluble in chloroform. Additionally, heating the solution with caffeine and tannin can help increase the solubility of caffeine, as solubility generally increases with temperature.
  • #1
Stratosphere
373
0
Is there any other way (besides experimentation) to know what chemicals react with other chemicals? Take this http://oxygen.chem.uidaho.edu/dschem276/Laboratory Experiments/Caffeine extraction from Coffee.pdf" for example, is there any other way to know that caffeine is soluble in water? And that tannin is NOT soluble in chloroform, but caffeine is?

Why would you have to heat the solution with the caffeine and the tannin in it in order for the caffeine to become soluble?
 
Last edited by a moderator:
Chemistry news on Phys.org
  • #2
Stratosphere said:
Is there any other way (besides experimentation) to know what chemicals react with other chemicals?

Yes. No.

Usually looking at the substance structure we can predict whether we should expect to dissolve in polar or non polar solvents, but reality has its own ways and sometimes our predictions are wrong. Experiment is the only 100% sure way of getting the answer.

Take this http://oxygen.chem.uidaho.edu/dschem276/Laboratory Experiments/Caffeine extraction from Coffee.pdf" for example, is there any other way to know that caffeine is soluble in water? And that tannin is NOT soluble in chloroform, but caffeine is?

It doesn't state tannin is not soluble in chloroform. It states that tannin reacts with carbonate to create a salt which is insoluble. That's nothing unusual - in general ionic salts are weakly soluble in non polar solvents, that's one of rules of thumb used to predict solubility.

Why would you have to heat the solution with the caffeine and the tannin in it in order for the caffeine to become soluble?

Solubility of most substances goes up with the temperature, counter examples do exist, but they are rare. It doesn't mean caffeine is insoluble in cold water - just its solubility is lover and dissolution is slow.

--
 
Last edited by a moderator:

1. How do we determine if a chemical reaction has occurred?

Chemical reactions can be identified through several observable changes, such as a color change, formation of a precipitate, release of gas, or change in temperature. These changes indicate that the reactants have been transformed into new products.

2. What factors can influence the rate of a chemical reaction?

The rate of a chemical reaction can be influenced by several factors, including temperature, concentration of reactants, surface area, and presence of a catalyst. Increasing temperature, concentration, and surface area can speed up the reaction, while adding a catalyst can lower the activation energy required for the reaction to occur.

3. How can we determine the yield of a chemical reaction?

The yield of a chemical reaction is the amount of product obtained compared to the amount of product that could theoretically be obtained. It can be determined through experimental measurements or through theoretical calculations based on the amount of reactants used and their stoichiometric ratios.

4. What is the difference between a physical and chemical change?

A physical change involves a change in the physical properties of a substance, such as state of matter or shape, but the chemical composition remains the same. In contrast, a chemical change results in the formation of new substances with different chemical properties.

5. How can we predict the products of a chemical reaction?

The products of a chemical reaction can be predicted by considering the reactants and their chemical properties, such as reactivity and bonding patterns. The use of chemical equations and knowledge of chemical reactions and their mechanisms can also aid in predicting the products of a reaction.

Similar threads

Replies
18
Views
2K
Replies
16
Views
2K
Replies
2
Views
2K
Replies
8
Views
2K
  • Chemistry
Replies
3
Views
7K
Replies
24
Views
5K
Replies
1
Views
2K
Replies
4
Views
2K
Replies
3
Views
893
Back
Top