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
MA_775_DIABLO [31]
3 years ago
12

A worker is exposed to the following airborne concentrations of ethylbenzene: 8:00 – 10:00 125 ppm 10:15 – 12:15 88 ppm 12:45 –

3:15 112 ppm 3:30 – 5:00 70 ppm What is the 8-hour TWA exposure for the employee (calculate the exposure)? Does it exceed the OSHA PEL?
Chemistry
1 answer:
postnew [5]3 years ago
8 0

Answer:

The 8-hour TWA exposure for the employee is 101 ppm and it exceeds the OSHA PEL of 100 ppm for ethylbenzene.

Explanation:

The TWA for 8 hours is calculated by the sum of airbone concentrations multiplied by the time it has been exposed to that period. The total is divided by 8 which refers to the 8 hours total the employee has been exposed.

TWA = (125x2+88x2+112x2.5+70x1.5)/8.

The OSHA PEL is a known number for every compound and it can be find in PEL tables. In the case of ethylbenezene, it is 100 ppm.

You might be interested in
2. What happens when hydrochloric acid (HCl) is added to the solution? Do the relative concentrations of H+, CH3COOH, or
iogann1982 [59]

Answer: A molecule of hydrochloric acid, for example, is composed of a hydrogen atom and a chlorine atom. When these molecules dissolve into water, they separate into a positively charged hydrogen ion and a negatively charged chlorine ion. ... Only some of the molecules of weak acids disassociate when added to water.

Explanation:

7 0
3 years ago
Read 2 more answers
How many moles of methanol must be added to 4.50 kg of water to lower its freezing point to -11.0 ∘c? for each mole of solute, t
DochEvi [55]

<u>Given:</u>

Mass of solvent water = 4.50 kg

Freezing point of the solution = -11 C

Freezing point depression constant = 1.86 C/m

<u>To determine:</u>

Moles of methanol to be added

<u>Explanation:</u>

The freezing point depression ΔTf is related to the molality m through the constant kf, as follows:

ΔTf = kf*m

where ΔTf = Freezing point of pure solvent (water) - Freezing pt of solution

ΔTf = 0 C - (-11.0 C) = 11.0 C

m = molality = moles of methanol/kg of water = moles of methanol/4.50 kg

11.0 = 1.86 * moles of methanol/4.50

moles of methanol = 26.613 moles

Ans: Thus around 26.6 moles of methanol should be added to 4.50 kg of water.



3 0
3 years ago
Which model of the atom explains the orbitals of electrons as waves
Zielflug [23.3K]

Answer:

The Bohr model of the atom explains the reactivity of all atoms.

6 0
2 years ago
How and why do ionic bonds form?
babymother [125]
Ionic bonds are formed when one of the two atoms that are reacting has excess electrons and transfer the electrons to the atom that is deficient in electrons. During the formation of the ionic bond, one of the reacting atoms will donate electrons and form positive ion.
7 0
3 years ago
What is the name of CuO? Explain how you determined the bond type and the steps you used to determine the naming convention for
yulyashka [42]

The name of CuO is copper II oxide and its bond type is ionic or electrovalent bond.

<h3>What is electrovalent bond?</h3>

An ionic or electrovalent bond is the type of chemical bond where two atoms or molecules are connected to each other by electrostatic attraction.

This electrostatic attraction is as a result of the transfer of electrons from the metallic element to the non-metal.

According to this question, CuO is a chemical compound consisting of two elements namely; copper and oxygen. The compound name is copper II oxide.

Copper as a metal transfers electrons to oxygen atoms, hence, an ionic bond is formed between the molecules.

Learn more about ionic bonds at: brainly.com/question/11527546

#SPJ1

4 0
1 year ago
Other questions:
  • Using stoichiometry, determine the mass of powdered drink mix needed to make a 1.0 M solution of 100 mL from C12H22O11
    13·1 answer
  • C8H10N4O2 is the chemical formula for caffeine, there are 8 carbons. List the 3 remaining elements in caffeine and how many atom
    5·1 answer
  • Can someone help me with this question please
    6·1 answer
  • A scientist is tracking an object orbiting the sun that is found between mars and Jupiter. Which additional feature can be used
    10·1 answer
  • CCC Patterns Changes in the state of matter (solid, liquid, gas) are the result of different energy levels at the molecular leve
    7·1 answer
  • Which substance can not be broken down by a chemical change? A)methane B)propanal C) tungsten D)water
    10·2 answers
  • _____ is a gel-like substance enclosed by the cell membrane that contains the cell's organelles. A) chloroplast B) cytoplasm C)
    6·2 answers
  • The pH of 0.10 M solution of an acid is 6. What is the percentage ionization of the acid?
    11·1 answer
  • How many moles are in 7.8g of CaO?
    15·1 answer
  • A hypothetical wave has 4.6 J of energy. What is its hypothetical, approximate frequency?
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!