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
Radda [10]
4 years ago
12

15 POINTS PLEASE HELP What volume of water must be added to 35mL of 2.6m KCl to reduce its concentration to 1.2m? Please explain

, as I have a quiz on this tomorrow and I really don't get this. Thanks so much!!
Chemistry
1 answer:
BartSMP [9]4 years ago
5 0
First, find the volume the solution needs to be diluted to in order to have the desired molarity:
You have to use the equation M₁V₁=M₂V₂ when ever dealing with dilutions.

M₁=the starting concentration of the solution (in this case 2.6M)
V₁=the starting volume of the solution (in this case 0.035L)
M₂=the concentration we want to dilute to (in this case 1.2M)
V₂=the volume of solution needed for the dilution (not given)

Explaining the reasoning behind the above equation:
MV=moles of solute (in this case KCl) because molarity is the moles of solute per Liter of solution so by multiplying the molarity by the volume you are left with the moles of solute.  The moles of solute is a constant since by adding solvent (in this case water) the amount of solute does not change.  That means that M₁V₁=moles of solute=M₂V₂ and that relationship will always be true in any dilution.

Solving for the above equation:
V₂=M₁V₁/M₂
V₂=(2.6M×0.035L)/1.2M
V₂=0.0758 L
That means that the solution needs to be diluted to 75.8mL to have a final concentration of 1.2M.

 Second, Finding the amount of water needed to be added:
Since we know that the volume of the solution was originally 35mL and needed to be diluted to 75.8mL to reach the desired molarity, to find the amount of solvent needed to be added all you do is V₂-V₁ since the difference in the starting volume and final volume is equal to the volume of solvent added.
75.8mL-35mL=40.8mL
40.8mL of water needs to be added

I hope this helps.  Let me know if anything is unclear.
Good luck on your quiz!
You might be interested in
Two words that describes the tone of "I know why the caged bird sings" and why
Mariulka [41]
Somber , knowledgeable 
3 0
4 years ago
Read 2 more answers
A 4-inch, f/5 telescope has a 1-inch eyepiece focal. Its magnifying power is:
Gre4nikov [31]

Its magnifying power is: 4X 5X 9X 20X. A 4-inch, f/5 telescope has a 1-inch eyepiece focal. Its magnifying power is 9x. This answer has been confirmed as correct and helpful.

7 0
3 years ago
Read 2 more answers
Classify each of these reactions. A single reaction may fit more than one classification. Ba ( ClO 3 ) 2 ⟶ BaCl 2 + 3 O 2 Ba(ClO
Lena [83]

Answer: a) Ba(ClO_3)_2\rightarrow BaCl_2+3O_2:  Decomposition

b) NaNO_2+HCl\rightarrow NaCl+HNO_2: double displacement

c) CaO+CO_2\rightarrow CaCO_3: Synthesis (Combination)

d) ZnSO_4+Mg\rightarrow MgSO_4+Zn: redox

Explanation:

Decomposition is a type of chemical reaction in which one reactant gives two or more than two products.

Ba(ClO_3)_2\rightarrow BaCl_2+3O_2

A double displacement reaction is one in which exchange of ions take place.

NaNO_2+HCl\rightarrow NaCl+HNO_2

Synthesis reaction is a chemical reaction in which two reactants are combining to form one product.

CaO+CO_2\rightarrow CaCO_3

Redox reaction is a type of chemical reaction in which oxidation and reduction takes place in one single reaction. The oxidation number of one element increases and the oxidation number of other element decreases.

ZnSO_4+Mg\rightarrow MgSO_4+Zn

4 0
3 years ago
How many miles of lead are equal to 9.51 x 10^3 g Pb?
Lemur [1.5K]
Molar mass Pb = 207.2 g/mol

1 mole Pb ------------- 207.2
? mole Pb ------------ 9.51 x 10³

moles = 9.51 x 10³ * 1 / 207.2

moles = 9.51 x 10³ / 207.2

= 45.89 moles

hope this helps!

7 0
3 years ago
Creating nuclear energy produces large amounts of radioactive waste.
Montano1993 [528]
Ummmm this one is hard but i guess it would be t?????

7 0
3 years ago
Other questions:
  • Assessment started: undefined.
    8·1 answer
  • Why does increasing the temperature of a reaction cause the reaction rate to increase?
    13·2 answers
  • Engineering applies blank And math to develop technology
    15·1 answer
  • 1. A weather balloon is filled with helium on a cool morning when the temperature is 13.0°C. The temperature is predicted to rea
    9·1 answer
  • Answer this if u know science please
    12·1 answer
  • Hey guys. whats with the account telling you to download a file. Is it dangerous?
    14·1 answer
  • Match the following terms to their correct definitions.
    10·1 answer
  • The process of adding hydrogen to the double bonds in unsaturated fatty acids to extend the shelf-life of food products is calle
    11·1 answer
  • More than half the total present volume of ocean water resides in what ocean?
    15·1 answer
  • A 25. 00 ml sample of acetic acid containing phenolphthalein indicator is titrated with 0. 1067 m naoh. The solution changes col
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!