This is a picture of a large sheet of ice that moves very slowly across the land. This sheet of ice covers the land and is

At 25 °C, how many dissociated OH– ions are there in 1243 mL of an aqueous solution whose pH is 2.07?

coldgirl [10]

Answer: The number of $OH^-$ ions dissociated are $8.57\times 10^{11}$

Explanation:

We are given:

pH = 2.07

Calculating the value of pOH by using equation, we get:

$2.07+pOH=14\\\\pOH=14-2.07=11.93$

To calculate hydroxide ion concentration, we use the equation to calculate pOH of the solution, which is:

$pOH=-\log[OH^-]$

We are given:

pOH = 11.93

Putting values in above equation, we get:

$11.93=-\log[OH^-]$

$[OH^-]=10^{-11.93}=1.17\times 10^{-12}M$

To calculate the number of moles for given molarity, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}$

Molarity of solution = $1.17\times 10^{-12}M$

Volume of solution = 1243 mL = 1.243 L (Conversion factor: 1 L = 1000 mL)

Putting values in above equation, we get:

$1.17\times 10^{-12}M=\frac{\text{Moles of }OH^-}{1.243L}\\\\\text{Moles of }OH^-=(1.17\times 10^{-12}mol/L\times 1.243L)=1.424\times 10^{-12}mol$

According to mole concept:

1 mole of a compound contains $6.022\times 10^{23}$ number of particles

So, $1.424\times 10^{-12}mol$ number of $OH^-$ will contain = $(1.424\times 10^{-12}\times 6.022\times 10^{23})=8.57\times 10^{11}$ number of ions

Hence, the number of $OH^-$ ions dissociated are $8.57\times 10^{11}$

3 0

3 years ago

What is the molarity of a 2.4-liter solution containing 124 grams of HF?

ioda

Molar mass:

HF = 1 + 19 = 20.0 g/mol

Number of moles :

124 / 20.0 => 6.2 moles

Volume = 2.4 L

M = n / V

M = 6.2 / 2.4

M = 2.6 M

Answer A

hope this helps!

7 0

3 years ago

Read 2 more answers

Which polyatomic ion is found in the compound represented by the formula NaHCO3?

olga nikolaevna [1]

Answer is (2) - hydrogen carbonate

Explanation:

NaHCO₃ is an ionic compound which is made from Na⁺ and HCO₃⁻ ions. The decomposition is

NaHCO₃ → Na⁺ + HCO₃⁻

Among the resulted ions, Na⁺ is a monatomic ion while HCO₃⁻ is a polyatomic ion.

Polyatomic ions mean ions which are made of two or more different atoms.

HCO₃⁻ is made from 3 atoms as H, C and O. The name of HCO₃⁻ ion is bicarbonate or hydrogen carbonate.

8 0

3 years ago

Examine the information.

lyudmila [28]

Vectors include magnitude & direction so the third option is the correct answer :)

8 0

2 years ago

Read 2 more answers

Suppose water contained some harmful volatile substance. How could you easily remove the volatile substance in a laboratory?

kari74 [83]

Well, you could use a reverse osmosis process to remove all of the fluoride that the United Staes government has put in the water! Every year the Us Gov receives a lot of fluoride from china. Fluoride is a waste and a poison, and instead of the Us Government paying a Buch of money to burn this waste, they just put it in the water! what you need t do, is get your water from the earth. Which is actually the best place to get your water, because its WATER filtered by the earth. Just google wells or springs around your location, some private business/companies offer their water collecting serves, something you should really take advantage of! As for me, I get my water at a place called "Carlsbad alkaline water." good stuff, only 50 cents for 4 gallons. rawr XD Jesus loves you, and he offers the everything freely, which means you don't need to follow a religion to earn anything. Lets face it, your not perfect, and we need help from God!

6 0

3 years ago