MathMaster logo

MathMaster

  1. Home
  2. general
  3. how much k2cr2o7 must be weighed and dissolved in distilled water to prepare 250 ml of a 2 mol l solution
Question

How much K2Cr2O7 must be weighed and dissolved in distilled water to prepare 250 mL of a 2 mol/L solution?

108

likes
541 views

Answer to a math question How much K2Cr2O7 must be weighed and dissolved in distilled water to prepare 250 mL of a 2 mol/L solution?

Expert avatar
Rasheed
4.7
103 Answers
1. Determine the molar mass of K_2Cr_2O_7:

M(K_2Cr_2O_7) = 2(39.1) + 2(52.0) + 7(16.0) = 294.2 \text{ g/mol}

2. Calculate the number of moles needed to prepare 250 mL (0.25 L) of a 2 mol/L solution:

n = C \cdot V = 2 \text{ mol/L} \times 0.25 \text{ L} = 0.5 \text{ mol}

3. Calculate the mass of K_2Cr_2O_7 required:

m = n \cdot M = 0.5 \text{ mol} \times 294.2 \text{ g/mol} = 147.1 \text{ g}

Frequently asked questions (FAQs)
What are the characteristics of an ellipse described by the equation (x-h)^2/a^2 + (y-k)^2/b^2 = 1?
+
What is the criteria for congruence of triangles?
+
What is the measure of an angle bisector if one angle measures 60° and the other angle measures 120°?
+
New questions in Mathematics
-8+3/5
How many percent is one second out a 24 hour?
6. Among 100 of products there are 20 rejects. We will randomly select 10 of products. The random variable X indicates the number of rejects among the selected products. Determine its distribution.
30. In 8 s, a car that starts from rest and moves with uniformly accelerated motion has achieved a speed of 72m/s. How much space must it travel to reach a speed of 90m/s? Sunshine: 450 m
Suppose 56% of politicians are lawyers if a random sample of size 564 is selected, what is the probability that the proportion of politicians who are lawyers will differ from the total politicians proportions buy more than 4% round your answer to four decimal places
Mrs. Emily saved RM10000 in a bank. At the end of the eighth year, the amount of money accumulated amounted to RM19992.71. If the bank pays an annual interest of x% for a year compounded every 6 months. Calculate the value of x.
. What will be the osmotic pressure of a solution that was prepared at 91°F by dissolving 534 grams of aluminum hydroxide in enough water to generate 2.784 ml of solution.
During a fishing trip Alex notices that the height h of the tide (in metres) is given by h=1−(1/2)*cos(πt/6) where t is measued in hours from the start of the trip. (a) Enter the exact value of h at the start of the trip in the box below.
show step by step simplification: (¬𝑑∨((¬b∧c)∨(b∧¬c)))∧((𝑎 ∧ 𝑏) ∨ (¬𝑎 ∧ ¬𝑏))∧(¬𝑐∨((¬𝑑∧𝑎)∨(𝑑∧¬𝑎)))
Nice's central library building is considered one of the most original in the world, as it is a mix between a sculpture and a work of habitable architecture. It was called La Tête Carrée and is made up of part of a bust that supports a cube divided into five floors. It is known that the building has a total height of approximately 30 meters. It admits that the cubic part of the sculpture is parallel to the floor and has a volume of 2744 meters3 Calculate, in meters, the height of the bust that supports the cube. Displays all the calculations you made.
I. Order to add 40.25+1.31+.45 what is the first action to do ?
7=-4/3y -1
Fill in the P(X-x) values to give a legitimate probability distribution for the discrete random variable X, whose possible values are -5 ,3 , 4, 5 , and 6.
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?
In an orchard there are 360 trees and they are distributed in 9 rows with the same number of trees in each row. 2 are rows of orange trees, 4 of apple trees and the rest are of pear trees. What fraction of the trees in the orchard are of each type of fruit tree? How many trees of each type are there?
A membership to the gym cost $25 per person in 1995. The membership cost has increased by an average $6 per person for each year since 1995. Write a linear equation for the cost of a gym membership for one person since 1995. What is the cost of a gym membership in 2009?
x(squared) -8x=0
Exercise The temperature T in degrees Celsius of a chemical reaction is given as a function of time t, expressed in minutes, by the function defined on ¿ by: T (t )=(20 t +10)e−0.5t. 1) What is the initial temperature? 2) Show that T' (t )=(−10 t +15)e−0 .5t. 3) Study the sign of T' (t ), then draw up the table of variations of T . We do not ask for the limit of T in +∞. 4) What is the maximum temperature reached by the reaction chemical. We will give an approximate value to within 10−2. 5) After how long does the temperature T go back down to its initial value? We will give an approximate value of this time in minutes and seconds. DM 2: study of a function Exercise The temperature T in degrees Celsius of a chemical reaction is given as a function of time t, expressed in minutes, by the function defined on ¿ by: T (t )=(20 t +10)e−0.5t. 1) What is the initial temperature? 2) Show that T' (t )=(−10 t +15)e−0.5 t. 3) Study the sign of T' (t ), then draw up the table of variations of T . We do not ask for the limit of T in +∞. 4) What is the maximum temperature reached by the reaction chemical. We will give an approximate value to within 10−2. 5) After how long does the temperature T go back down to its initial value? We will give an approximate value of this time in minutes and seconds.
To apply a diagnostic test, in how many ways can 14 students be chosen out of 25? if the order does not matter
A plant found at the bottom of a lake doubles in size every 10 days. Yeah It is known that in 300 days it has covered the entire lake, indicate how many days it will take to cover the entire lake four similar plants.

You might be interested in