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)
What is the value of f(x) = 7 when x = 5?
+
What is the relationship between the lengths of the corresponding sides and angles of congruent triangles?
+
Math question: What is the maximum value of the function f(x) = 2x^3 - 5x^2 + 4x - 3 on the interval [-1, 3]?
+
New questions in Mathematics
𝑦 = ( 𝑥2 − 3) (𝑥3 + 2 𝑥 + 1)
a ferry travels 1/6 of the distance between two ports in 3/7 hour. The ferry travels at a constant rate. At this rate, what fraction of the distance between the two ports can the ferry travel in one hour.
Revenue Maximization: A company sells products at a price of $50 per unit. The demand function is p = 100 - q, where p is the price and q is the quantity sold. How many units should they sell to maximize revenue?
Find the equation of the normal to the curve y=x²+4x-3 at point(1,2)
3(4×-1)-2(×+3)=7(×-1)+2
A car that starts from rest moves for 11 min, reaching a speed of 135 km/h, calculate the acceleration it had
The director of a company must transfer 6 people from the human resources department to the sales department, in order to sustain sales during the month of December. What is the probability that he will transfer only 2 of them?
Margin of error E=0.30 populations standard deviation =2.5. Population means with 95% confidence. What I the required sample size (round up to the whole number)
The function g:Q→Q is a ring homomorphism such that g(3)=3 and g(5)=5. What are the values of g(8) and g(9)?
15/5+7-5
The thermal representation f(x) = 20 times 0.8 to the power of x is known from an exponential function f. Specify the intersection point with the y-axis
7=-4/3y -1
In an audience of 4000 people, 2 people are chosen, at random, to appear on stage. How many ways can the people be chosen?
What is 75 percent less than 60
a survey showed that 3 out of 7 voters would vote in an election. based on this survey, how many people would vote in a city with 25,000 people?
nI Exercises 65-68, the latitudes of a pair of cities are given. Assume that one city si directly south of the other and that the earth is a perfect sphere of radius 4000 miles. Use the arc length formula in terms of degrees to find the distance between the two cities. 65. The North Pole: latitude 90° north Springfield, Illinois: latitude 40° north
A person runs 175 yards per minute write a variable that represents the relationship between time and distance
Find the equation of a straight line that has slope 3 and passes through the point of (1, 7) . Write the equation of the line in general forms
A triangle is cut by a line s parallel to the base in such a way that it divides the side of the triangle into parts in the ratio of 2 : 3. Find the other side of the triangle if it is known that the line s divides it into parts whose length is 5 cm.
23,456 + 3,451