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
Yuri [45]
3 years ago
15

The density of thorium, which has the FCC structure, is 11.72 g/cm3. The atomic weight of thorium is 232 g/mol. Calculate (a) th

e lattice parameter; and (b) the atomic radius of thorium.

Chemistry
2 answers:
seropon [69]3 years ago
4 0

Answer:

(a) a = 5.08x10⁻⁸ cm

(b) r = 179.6 pm  

Explanation:

(a) The lattice parameter "a" can be calculated using the following equation:

\rho = \frac{(N atoms/cell)*m}{V_{c}*N_{A}}      

<em>where ρ: is the density of Th = 11.72 g/cm³, N° atoms/cell = 4, m: is the atomic weight of Th = 232 g/mol, Vc: is the unit cell volume = a³, and </em>N_{A}<em>: is the Avogadro constant = 6.023x10²³ atoms/mol. </em>

Hence the lattice parameter is:  

a^{3} = \frac{(N atoms/cell)*m}{\rho *N_{A}} = \frac{4 atoms*232 g/mol}{11.72 g/cm^{3} *6.023 \cdot 10^{23} atoms/mol} = 1.32 \cdot 10^{-22} cm^{3}

a = \sqrt[3]{1.32 \cdot 10^{-22} cm^{3}} = 5.08 \cdot 10^{-8} cm

(b) We know that the lattice parameter of a FCC structure is:

a = \frac{4r}{\sqrt{2}}

<em>where r: is the atomic radius of Th</em>

Hence, the atomic radius of Th is:

r = \frac{a*\sqrt{2}}{4} = \frac{5.08 \cdot 10^{-8} cm*\sqrt{2}}{4} = 1.796 \cdot 10^{-8} cm = 179.6 pm    

I hope it helps you!    

mario62 [17]3 years ago
3 0

Explanation:

Below is an attachment containing the solution

You might be interested in
Method that used to separate kerosine and water?
nata0808 [166]
You can use a separating funnel. The person will go the top and the water to the bottom.
7 0
3 years ago
Read 2 more answers
Energy is released when the nucleus of an atom splits and two smaller atoms are formed. What is the name of this process?
Svetllana [295]

Explanation:

It's (D), nuclear fission................

5 0
2 years ago
A sample of hydrogen gas was collected over water. If the total pressure
Brut [27]
It would 47.7 because you would have to both minus the number together.
7 0
3 years ago
In a physical change of matter,​
mel-nik [20]

Answer: C. no new substances are formed<span>
</span><span>
<span>In the physical change of matter, there is no new substance that is formed. It is only the appearance of the matter that is being changed and not its chemical composition. Cutting, tearing and grinding are only some of the examples that exhibit physical change. </span></span>

5 0
3 years ago
Read 2 more answers
7. There are 7. 0 ml of 0.175 M H2C2O4 , 1 ml of water , 4 ml of 3.5M KMnO4 what is the molar concentration ofH2C2O4 ?
Illusion [34]

Answer:

7. 0.1021 M

8. 1.167 M

10. Increase in volume of water would lower the rate of reaction

Explanation:

7. What is the molar concentration of H₂C₂O₄ ?

Since we have 7.0 ml of 0.175 M H₂C₂O₄, the number of moles of H₂C₂O₄ present n = molarity of H₂C₂O₄ × volume of H₂C₂O₄ = 0.175 mol/L × 7.0 ml = 0.175 mol/L × 7 × 10⁻³ L = 1.225 × 10⁻³ mol.

Also, the total volume present V = volume of H2C2O4 + volume of water + volume of KMnO4 = 7.0 ml + 1 ml + 4 ml = 12 ml = 12 × 10⁻³ L

So, the molar concentration of H₂C₂O₄, M = number of moles of H₂C₂O₄/volume = n/V

= 1.225 × 10⁻³ mol/12 × 10⁻³ L

= 0.1021 mol/L

= 0.1021 M

8. Using the data from question 7 what is the molar concentration of KMnO₄ ?

Since we have 4.0 ml of 3.5 M KMnO₄, the number of moles of KMnO4 present n' = molarity of KMnO₄ × volume of KMnO₄ = 3.5 mol/L × 4.0 ml = 3.5 mol/L × 4 × 10⁻³ L = 14 × 10⁻³ mol.

Also, the total volume present V = volume of KMnO₄ + volume of water + volume of KMnO₄ = 7.0 ml + 1 ml + 4 ml = 12 ml = 12 × 10⁻³ L

So, the molar concentration of KMnO₄, M' = number of moles of KMnO₄/volume = n'/V

= 14 × 10⁻³ mol/12 × 10⁻³ L

= 1.167 mol/L

= 1.167 M

10. From question number 7, what effect increasing the volume of water has on the reaction rate?

Increase in volume of water would lower the rate of reaction because, the particles of both substances would have to travel farther distances to collide with each other, since there are less particles present in the solution and thus, the concentration of the particles would decrease thereby decreasing the rate of reaction.

3 0
3 years ago
Other questions:
  • While elements and compounds can both be classified as pure substances because they have distinct properties and composition, __
    10·2 answers
  • When one form of energy is converted to another form in any physical or chemical change, energy input alwasy equals energy outpu
    14·1 answer
  • Which of the following is an example of representative money?
    8·1 answer
  • The area surrounding the nucleus is called: protons electrons neutrons electron cloud
    7·2 answers
  • Gasoline has a density of 0.749 g/mL. There are 454 grams in a pound and 3.7854 litres in a gallon. How many pounds does 19.2 ga
    15·1 answer
  • Statement 1: The reaction follows the mass energy equation E= mc". Statement 2: A large amount of energy is produced during the
    10·1 answer
  • Which of the following statements is true?
    15·2 answers
  • The earth's crust is part of which sphere?​
    7·1 answer
  • Name the functional group in the
    15·1 answer
  • A container is filled with helium gas. It has a volume of 2.25 liters and contains 9.00 moles of helium. How many moles of heliu
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!