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Thirty grams of potassium chloride crystals are added to 400 mL of water. What is the molarity of this potassium chloride solution?

A.
1.0 M
B.
13.3 M
C.
0.186 M
D.
0.075 M

User Shadysamir
by
5.3k points

2 Answers

5 votes

Answer:

A

Step-by-step explanation:

User Shane Hathaway
by
5.2k points
2 votes

Answer:

Molarity of potassium chloride is:

A. 1.0 M

Step-by-step explanation:

Molarity is used to express the concentration of the solution.It is defined as the moles of solutes per liter volume of solution.It is denoted by M.


<strong>molarity(M)=(moles\ of\ solute)/(volume\ of\ solution(ml))* 1000</strong>


<strong>M=(n)/(V(ml))* 1000</strong>

Here'n' is the number of moles. It can be calculated using formula:


<strong>n=(given\ mass(w))/(molar\ mass</strong>)

given mass=30 gm

Molar mass of KCl = mass of K+mass of Cl

= 39.098+34.45

= 74.55 g


<strong>n=(30)/(74.55)</strong>

n = 0.402 moles


<strong>M=(n)/(V(ml))* 1000</strong>


<strong>M=(0.402)/(400)* 1000</strong>


M=\0.001* 1000

M=1.00 M

So molarity of potassium chloride is 1.00 M

User Maxkfranz
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