1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Effectus [21]
3 years ago
10

When matter changes from one state of matter to another it is called_________.

Chemistry
1 answer:
Serhud [2]3 years ago
4 0

Answer:

c physical change

Explanation:

You might be interested in
Anyone know the answer
kodGreya [7K]

Answer:

a and d

Explanation:

a bromine and the calcium atom loses two elections

6 0
2 years ago
Which of the statements below is not a characteristic of economically developed nations?
nikklg [1K]
I would go with option #4, reduced use of resources!

:V
6 0
3 years ago
Read 2 more answers
Which of the following pairs of compounds have the same empirical formula?
andreyandreev [35.5K]

Answer:

option a and c both are correct

Explanation:

please mark me as brainliest

6 0
2 years ago
What happens to carbon compounds in air when heated sufficiently?
madreJ [45]
They may break bonds,form new compounds, new ions etc...
3 0
2 years ago
12. Which compound can act as both a BrønstedLowry
oksian1 [2.3K]
1) The compound which can act as a <span>Bronsted-Lowry acid and a Bronsted-Lowry base is definitely water - H2O. Remember that water is </span><span>amphoteric which means it can </span>either accept protons or donate them, so it is the most proper option among other represented. Here are examples of both base and acid with water : <span>HCl+H20=H30+Cl ; </span><span>NH3+H2O=NH4+OH 

2) The </span><span>acids in this equilibrium reaction CN– + H2O HCN + OH. Acid species always donate </span> H+ to the species with which they react. In the second option you can see how H2O donates an H+ to CN-. If the reaction gets reversed we will obtain<span> HCN that donates an H+ to OH that shows that it is an acid.
</span><span>
3) </span>The products of self-ionization of water are OH⁻ and H₃O⁺. Self-ionization is an ionization reaction during which  H2O deprotonates its hydrogen atoms to become a hydroxide ion -- OH−. After this process OH-  protonates another water molecule forming H3O+<span>. 

4) The type of </span> solution which is one with a pH of 8 is acidic. Here is a little table that can be a prompt for you if you ever come across such tasks - ph : 7 is neutral<span>. </span>pH<span>  </span>lower than 7<span> are acidic, and </span>pH<span>  higher than </span>7<span> basic ones. 

5) </span><span>The acid dissociation constant for an acid dissolved in water is equal to the equilibrium constant. I consider this option correct because we can obtan </span><span>Kw only when dealing with Kb, and we can conclude that the hydrolysis constant of the conujugate base. 

6) </span>A 0.12 M solution of an acid that ionizes only slightly in solution would be termed dilute and weak. You can determine it depending on its concentration. Such value as 0.12M usually defined as a dilute solution of a weak acid due to the fact that acid represents its <span>partial ionization which is a direct characteristic of a weak acid.
 
7) To solve this task we should appeal to H</span>enry's law that says<span> the solubility of a gaz is proportional to its partial pressure. And according to this we can understand that </span>202kPa is the half of 404kPa which means that the needed solubility must be divided by <span>2 7.5/2=3.75 g/L and that's all.

8) I think that the most important points which best show </span><span>how the addition of a solute affects the boiling point, the freezing
point, and the vapor pressure of the solvent are : BOILING: a</span>dditional attractive forces can only exist between solute and solvent and in order to boil they must be overcome for the solution;we should add KE to overcome the forces. FREEZING : to freeze we have to withdrawn KE as the solute particles are surrounded by solvent molecules. VAPOR : WHen <span>solvent shells are being formed  the solute particles reduces the number of solvent particles that have sufficient KE to vaporize.</span>
<span>
9) </span>[H+][OH-]= Kw = 1.0 * 10^-14
[H+]= Kw/ [OH-]= 1.0x 10^-14 / 1 x 10^-11 =1 x 10^-3 mol/L &#10;&#10;pH = - log [H+]= - log 1 x 10^-3 = 3
Since we got Ph of 3 in a result we can define solution as an acidic one, as I mentioned before.

10) Since the formula of the given acid is HA it undergoes like that :<span> HA<=> H+ + A- .
</span><span>ka = [H][A] / [HA].
Now we have only </span>[H+] and to go further you need to write  <span>electroneutrality equation for the reaction :
</span>[H+] = [OH-] + [A-]  (since [H]>>>[OH]), then 
<span>[H+] = [A-] 
</span>Then mass balance equation : 
Ct = 0.5M = [A-] + [HA] 
<span>[HA] = 0.5 - [A-] = 0.5 - [H+] 
</span>Finally here is what we have done and get : 
ka = [H]^2 / (0.5 - [H+]) &#10;
ka = 0.0001*0.0001/(0.5-0.0001) = 2.00x10^-8

11) The main points that are common for acids : they form Hydrogen ions when dissloved in water, - Ex. Vinegar and Lemon, Ph >7, they have <span>Increased hydrogen ions (H+). The facts about bases : they r</span>educe the concentration of hydgoren ions in a solution which is opposite to asids,<span>- Ex. Antiacid,and Ammonia ,</span>Ph valuse above 7, they form hydrogen (OH-).
- The common points of both acids and bases : <span>Hydrogen ions ,</span>
 both not neutral and water based.
5 0
2 years ago
Other questions:
  • Based on the table what conclusion can the student make about relationships between elements
    8·1 answer
  • Through the process of photosynthesis, _ energy is transformed into _ energy
    10·2 answers
  • Prelab for Experiment 4: The Atomic Theory of Matter 1. Demonstrate the Law of Multiple Proportions with the following data: a.
    7·1 answer
  • An experiment was conducted with a 1.57 gram starting mass of copper. How many grams of cooper were collected if the yield was 8
    8·1 answer
  • What is the empirical formula of a molecule containing 65.5% carbon, 5.5% hydrogen, and 29.0% oxygen?
    5·1 answer
  • 3. Students in a science class in Marfa, Texas, made a poster with a diagram to represent a seasonal change in the Northern Hemi
    14·1 answer
  • Will Upvote!
    5·2 answers
  • In a unimolecular reaction with seven times as much starting material as product at equilibrium, what is the value of keq?
    15·1 answer
  • Please help does anybody know how to calculate the molar mass of a compound?
    5·2 answers
  • in 4 season countries, the temperatire may drop till below 0°c during the peak of winter. why does the surface of the river or l
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!