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
Elan Coil [88]
3 years ago
13

A chemistry student must write down in her lab notebook the concentration of a solution of sodium hydroxide. The concentration o

f a solution equals the mass of what's dissolved divided by the total volume of the solution.
Here's how the student prepared the solution:

She put some solid sodium hydroxide into the graduated cylinder and weighed it. With the sodium hydroxide added, the cylinder weighed. She added water to the graduated cylinder and dissolved the sodium hydroxide completely. Then she read the total volume of the solution from the markings on the graduated cylinder. The total volume of the solution was .

What concentration should the student write down in her lab notebook?
Chemistry
1 answer:
taurus [48]3 years ago
6 0

Answer:

The concentration the student should write down in her lab is 2.2 mol/L

Explanation:

Atomic mass of the elements are:

Na: 22.989 u

S: 32.065 u

O: 15.999 u

Molar mass of sodium thiosulfate, Na2S2O3 = (2*22.989 + 2*32.065 + 3*15.999) g/mol = 158.105 g/mol.

Mass of Na2S2O3 taken = (19.440 - 2.2) g = 17.240 g.

For mole(s) of Na2S2O3 = (mass taken)/(molar mass)

= (17.240 g)/(158.105 g/mol) = 0.1090 mole.

Volume of the solution = 50.29 mL = (50.29 mL)*(1 L)/(1000 mL)

= 0.05029 L.

To find the molar concentration of the sodium thiosulfate solution prepared we use the formula:

= (moles of sodium thiosulfate)/(volume of solution in L)

= (0.1090 mole)/(0.05029 L)

= 2.1674 mol/L

You might be interested in
You are
timama [110]
Eye protection, fire proof clothing, proper foot gear, just anything that you could prevent yourself from being burned because you are working with flammable materials.
8 0
2 years ago
Electron configuration worksheet
MrMuchimi

Answer:

bro please rotate it and send again please

5 0
2 years ago
Predict whether the following reactions will be exothermic or endothermic.
Solnce55 [7]

Answer:

A. N₂(g) + 3H₂(g) -----> 2NH₃    exothermic

B. S(g) + O₂(g) --------> SO₂(g)    exothermic

C. 2H₂O(g) --------> 2H₂(g) + O₂(g) endothermic

D. 2F(g) ---------> F₂(g) exothermic

Explanation:

The question says predict not calculate. So you have to use your chemistry knowledge, experience and intuition.

A. N₂(g) + 3H₂(g) -----> 2NH₃    is exothermic because the Haber process gives out energy

B. S(g) + O₂(g) --------> SO₂(g)    is exothermic because it is a combustion. The majority, if not all, combustion give out energy.

C. 2H₂O(g) --------> 2H₂(g) + O₂(g) is endothermic because it is the reverse reaction of the combustion of hydrogen. If the reverse reaction is exothermic then the forward reaction is endothermic  

D. 2F(g) ---------> F₂(g) is exothermic because the backward reaction is endothermic. Atomisation is always an endothermic reaction so the forward reaction is exothermic

5 0
3 years ago
A Brønsted-Lowry acid Question 9 options: A) has a lower pH than vinegar. B) is any species that donates a proton. C) is any spe
rusak2 [61]

Answer:

B) is any species that donates a proton.

7 0
3 years ago
1. What are the possible genotypes of offspring when crossing BB, Bb parents?
marissa [1.9K]

Answer:

1, C: BB, Bb, Bb, BB

2. C: Hybrid

Explanation:

1. If u do a punnet square for BB and Bb you will get: BB, Bb, Bb, Bb

B| B|

B| BB. BB

b| Bb Bb

2. You do a punnet square for BB and bb and you'll get: Bb, Bb, Bb, Bb, which means all the children are hybrids of Dominant alleles ans recessive alleles

<u>B </u> <u>B</u>

b| Bb Bb

b| Bb Bb

4 0
3 years ago
Read 2 more answers
Other questions:
  • CAN SOMEONE PLEASE WRITE ME SHORT STORY FOR THIS. I'LL GIVE YOU BRAINLIEST. I PROMISE. 98 POINTS
    6·1 answer
  • Which statement about subatomic particles is NOT true?
    14·2 answers
  • Predict the products of the reaction below. That is, complete the right-hand side of the chemical equation. Be sure your equatio
    14·1 answer
  • Red paint mixed with blue paint becomes purple. What is the most likely cause of this color change?
    14·1 answer
  • The table shows the concentration of a reactant in the reaction mixture over a period of time.
    11·1 answer
  • This is a property of matter that can be identified without changing the identity of the substance
    14·1 answer
  • What is the volume, in liters, of 0.500 mol of c3 h8 gas at stp?
    15·1 answer
  • How do you explain density column?
    8·1 answer
  • Which of the following would have the highest entropy?
    13·1 answer
  • A farmer has a bucket of fertilizer that will help her plants grow. She
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!