Question

Potassium dichromate, also called potassium bichromate, is an orange-red crystalline solid, K2Cr2O7, soluble in water and insoluble in alcohol. What is the molar concentration of this salt in a solution whose chromium ion concentration is 5.72 mg/mL? Data: K=39; Cr=52 and O=16 g/mol. NOTE: The answer must have 3 places after the comma, to avoid rounding errors.

55

likes
275 views

Answer to a math question Potassium dichromate, also called potassium bichromate, is an orange-red crystalline solid, K2Cr2O7, soluble in water and insoluble in alcohol. What is the molar concentration of this salt in a solution whose chromium ion concentration is 5.72 mg/mL? Data: K=39; Cr=52 and O=16 g/mol. NOTE: The answer must have 3 places after the comma, to avoid rounding errors.

Expert avatar
Santino
4.5
112 Answers
\text{Concentração de íons crômio em g/L} = 5.72 \times 10^{-3} \, \text{g/mL} \times 1000 \, \text{mL/L}

\text{Concentração de íons crômio em g/L} = 5.72 \, \text{g/L}

\text{Massa molar de } Cr = 52 \, \text{g/mol}

\text{Número de mols de } Cr = \frac{5.72 \, \text{g/L}}{52 \, \text{g/mol}}

\text{Número de mols de } Cr = 0.110 \, \text{mol/L}

K_2Cr_2O_7 \rightarrow 2K^+ + 2Cr^{3+} + 7O^{2-}

[Cr^{3+}] = 2 [K_2Cr_2O_7]

0.110 \, \text{mol/L} = 2 [K_2Cr_2O_7]

[K_2Cr_2O_7] = \frac{0.110}{2} \, \text{mol/L}

[K_2Cr_2O_7] = 0.055 \, \text{mol/L}

\text{Answer: } 0.055 \, \text{mol/L}

Frequently asked questions (FAQs)
Math question: "Factorize the expression x^2 + 8x + 15 using the quadratic formula."
+
How many centimeters are in 1.8 meters?
+
Question: Solve the inequality 3x + 5 < 10 for x.
+
New questions in Mathematics
A=m/2-t isolate t
1 + 1
-6n+5=-13
A normally distributed population has a mean of 118 with a standard deviation of 18. What score separates the lowest 72% of the distribution from the rest of the scores?
Let X be a discrete random variable with range {1, 3, 5} and whose probability function is f(x) = P(X = x). If it is known that P(X = 1) = 0.1 and P(X = 3) = 0.3. What is the value of P(X = 5)?
By differentiating the function f(x)=(x³−6x)⁷ we will obtain
Suppose 50% of the doctors and hospital are surgeons if a sample of 576 doctors is selected what is the probability that the sample proportion of surgeons will be greater than 55% round your answer to four decimal places
(2x+5)^3+(x-3)(x+3)
7/6-(-1/9)
2x+4x=
find f(x) for f'(x)=3x+7
suppose random variable x follows poisson distribution with expected value 3. what is variance of x?
A storage maker price is $2.50 per square feet. Find the price of a custom shed 4 yards long, and 5yards wide and 8 feet tall
1. A capital of $3,831 was lent, and it has produced interest of $840 from 05-12-2022 to 1-12-2023. At what annual simple interest rate was the capital lent?
-1%2F2x-4%3D18
For what values of m is point P (m, 1 - 2m) in the 2⁰ quadrant?
Find the zero of the linear function 8x + 24 = 0
X^X =49 X=?
A group of 17 people spent 9 days on vacation and spent R$776.34 on barbecue meat and the bill needs to be divided as follows: 6 people stayed for 9 days, 7 people stayed for 4 days, and 2 people stayed for 5 days and 2 people stayed 3 days, how much does each group have to pay for the days they stayed?
The perimeter of a rectangular rug is 42 feet. The width is 9 feet. What is the length?