1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
lawyer [7]
3 years ago
9

Dilution question In many of the experiments, you will be asked to prepare a standard solution by diluting a stock solution. You

will be specifically asked how you will do the dilution steps during the review before you start work. Here is a homework question to get you to think about this process. You have a 1000 ug/mL stock solution of lead (Pb2+). Describe how you would prepare a 100 ppb standard solution from this stock solution. Rules: No single dilution step can be greater than 1:50 You have 25.00 mL volumetric flasks and 10.00 mL volumetric flasks. You have access to three pipet dispensers. One dispenser delivers between 1 and 5 mL, the second dispenser delivers between 100 and 1000 , and the third dispenser delivers between 20 and 200 HL
Chemistry
1 answer:
riadik2000 [5.3K]3 years ago
6 0

Answer:

We could do two 1:50 dilutions and one 1:4 dilutions.

Explanation:

Hi there!

A solution that is 1000 ug/ ml  (or 1000 mg / l) is 1000 ppm.

Knowing that 1 ppm = 1000 ppb, 100 ppb is 0.1 ppm.

Then, we have to dilute the stock solution (1000 ppm / 0.1 ppm) 10000 times.

We could do two 1:50 dilutions and one 1:4 dilutions (50 · 50 · 4 = 10000). Since the first dilution is 1:50, you will use the smallest quantity of the stock solution (if we use the 10.00 ml flask):

First step (1:50 dilution):

Take 0.2 ml of the stock solution using the third dispenser (20 - 200 ul), and pour it in the 10.00 ml flask. Fill with water to the mark (concentration : 1000 ppm / 50 = 20 ppm).

Step 2 (1:50 dilution):

Take 0.2 ml of the solution made in step 1 and pour it in another 10.00 ml flask. Fill with water to the mark. Concentration 20 ppm/ 50 = 0.4 ppm)

Step 3 (1:4 dilution):

Take 2.5 ml of the solution made in step 3 (using the first dispenser 1 - 5 ml) and pour it in a 10.00 ml flask. Fill with water to the mark. Concentration 0.4 ppm / 4 = 0.1 ppm = 100 ppb.

You might be interested in
Balance chemical equation Fe3O4 = Fe + CO2
m_a_m_a [10]

equation Fe3O4=Fe+CO2 is an impossible reaction

5 0
3 years ago
How is oxide different from a neutral oxygen atom
Zepler [3.9K]

Answer: The main difference between oxide and oxygen is that oxide is a chemical compound with at least one oxygen atom while oxygen is an element whose atomic number is 8.

Explanation: let me know if it was right or wrong

4 0
2 years ago
How to describe a ufo??​
erastova [34]

Answer:

Unidentified flying object or fly saucer.

Explanation:

6 0
2 years ago
Read 2 more answers
A gas is at a pressure of 4.30 atm. what is this pressure in kilopascals? in mm hg?
Monica [59]
Units to measure pressure are as follows
atm - atmospheric pressure units
kPa - kilo Pascals
mm Hg - milimeters Hg
conversion units are;
 1 atm = 101 325 Pa
therefore 4.30 atm = 101 325 Pa / atm x 4.30 atm = 435.7 Pa

1 atm = 760.0 mm Hg
 4.30 atm = 760.0 mm Hg / atm x 4.30 atm = 3268 mm Hg

answers are 435.7 Pa and 3268 mm Hg
5 0
3 years ago
Read 2 more answers
What is this what is this
monitta

Answer:Attemted Failed

Maybe try to search

In a different way like:

what is the ingredient of cake

Instead of

how to make Cake

5 0
3 years ago
Other questions:
  • What mass of calcium carbonate must be heated strongly to produce 1.12g of calcium oxide?
    11·2 answers
  • Is glucose a solution colloid or suspension?
    7·1 answer
  • Find the volume of 10g of gasoline if it has a density of 0.7g/mL
    9·1 answer
  • Be sure to answer all parts. Sulfonation of benzene has the following mechanism: (1) 2 H2SO4 ⇌ H3O+ + HSO4− + SO3 [fast] (2) SO3
    13·1 answer
  • As a Ca atom undergoes oxidation to Ca2+, the number of neutrons in its nucleus
    14·2 answers
  • A monatomic ion with a charge of 2 has an electronic configuration of 1s22s22p6. This ion is a(n) _______ . What is the chemical
    13·1 answer
  • Cell membranes are selectively permeable. This means that A. only water can move freely across the cell membrane. B. any substan
    11·1 answer
  • Oxygen has 8 positively charged protons what is the number of negatively charged electrons in an atom of oxygen?
    15·1 answer
  • The number of gas molecules in a container is doubled. How will the pressure in the container change if the temperature and volu
    8·1 answer
  • 2) Imagine that a loudspeaker is producing quiet note with a low pitch
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!