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
ANEK [815]
2 years ago
9

Zinc oxide adopts a face-centered cubic arrangement. Both Zinc ions and oxide ions adopt the face-centered cubic arrangement; wi

th the unit cell defined by the cations overlapping the unit cell defined by the anions. What is the mass of one unit cell of zinc oxide?
Chemistry
1 answer:
vichka [17]2 years ago
3 0

Answer:

5.41 ×10⁻²²

Explanation:

We were told right from the question that both the Zinc ions and the Zinc oxide adopts a face-centered cubic arrangement.

Then, the number of ZnO molecule in one unit cell = 4

The standard molar mass of ZnO = 81.38g

Avogadro's constant = 6.023 × 10²³ mole

∴

The mass of one unit cell of zinc oxide can be calculated as:

= \frac{4*81.38}{6.023*10^{23}}

= 5.40461564×10⁻²²

≅ 5.41 ×10⁻²²

∴ The mass of one unit cell of zinc oxide = 5.41 ×10⁻²²

You might be interested in
How does Gregor Mendel's work with pea plants affect human life today? OA A. People continue to cross pea plants to fix Mendel's
lana [24]

Answer:

B

Explanation:

Not sure, but that one makes the most since

4 0
3 years ago
The dissociation of sulfurous acid (H2SO3) in aqueous solution occurs as follows:
aksik [14]

Answer:

The [SO₃²⁻]

Explanation:

From the first dissociation of sulfurous acid we have:

                         H₂SO₃(aq) ⇄ H⁺(aq) + HSO₃⁻(aq)

At equilibrium:  0.50M - x          x            x

The equilibrium constant (Ka₁) is:

K_{a1} = \frac{[H^{+}] [HSO_{3}^{-}]}{[H_{2}SO_{3}]} = \frac{x\cdot x}{0.5 - x} = \frac {x^{2}}{0.5 -x}

With Ka₁= 1.5x10⁻² and solving the quadratic equation, we get the following HSO₃⁻ and H⁺ concentrations:

[HSO_{3}^{-}] = [H^{+}] = 7.94 \cdot 10^{-2}M

Similarly, from the second dissociation of sulfurous acid we have:

                              HSO₃⁻(aq) ⇄ H⁺(aq) + SO₃²⁻(aq)

At equilibrium:  7.94x10⁻²M - x          x            x

The equilibrium constant (Ka₂) is:  

K_{a2} = \frac{[H^{+}] [SO_{3}^{2-}]}{[HSO_{3}^{-}]} = \frac{x^{2}}{7.94 \cdot 10^{-2} - x}  

Using Ka₂= 6.3x10⁻⁸ and solving the quadratic equation, we get the following SO₃⁻ and H⁺ concentrations:

[SO_{3}^{2-}] = [H^{+}] = 7.07 \cdot 10^{-5}M

Therefore, the final concentrations are:

[H₂SO₃] = 0.5M - 7.94x10⁻²M = 0.42M

[HSO₃⁻] = 7.94x10⁻²M - 7.07x10⁻⁵M = 7.93x10⁻²M

[SO₃²⁻] = 7.07x10⁻⁵M

[H⁺] = 7.94x10⁻²M + 7.07x10⁻⁵M = 7.95x10⁻²M

So, the lowest concentration at equilibrium is [SO₃²⁻] = 7.07x10⁻⁵M.

I hope it helps you!

8 0
3 years ago
100.mL of a .795 M solution of KBr is diluted to 500.mL. what is the new concentration of the solution?
kap26 [50]

Answer:

0.159 M

Explanation:

convert from mL to L then use the equation:

M1V1 = M2V2

rearrange to find M2

\frac{M1V1}{V2} = M2

\frac{(0.795 M)(0.100 L)}{0.500 L} = 0.159 M

4 0
2 years ago
Which of these is NOT a cause of the heat inside Earth?
Andrei [34K]

Answer:

Bombardment by asteroids

Explanation:

All of the other ones explain themselves

6 0
3 years ago
Read 2 more answers
Match the chemical with the statement that best describes the observed change in the rate of the reaction when the concentration
maria [59]

Answer:

Explanation:

When the amount of H2O2 is doubled while KI is kept constant, the rate of reaction doubles.

When the amount of KI is doubled and the amount of H2O2 is halved, the rate stays nearly constant.

2H2O2 (aq) → O2(g) + 2H2O (l) ------------- first order kinetics reaction.

Catalysts are KI, FeCl3 only, KCl is not a catalyst. Order: KI < MnO2 < Pb < FeCl3.

H2O2 + I– -> IO– + H2O (Step 1)

H2O2 + IO– -> I– + H2O + O2 (Step 2)

It can be seen that the iodine ion (provided by the KI solution) is a product as well as a reactant.

02(g)2Fe? (aq) + 2 H(a) 2 H 2 Fe3 (aq) H2O2(aq) + 2 Fe,Taq) H02(aq) 2 Fe (aq) 2 H (aq)

8 0
2 years ago
Other questions:
  • Anyone know what the answer is??
    7·1 answer
  • Convert 0.02 g/mL to the unit g/L.
    15·1 answer
  • Which of the following is true of the mass of an object?
    13·1 answer
  • If aluminum has a mass of 22.3 g, how many liters of oxygen gas are required at STP?
    13·1 answer
  • Darwins view of the evolution of the giraffe was
    10·1 answer
  • What is thermodynamics ??? <br>don't explain .-. !!!​
    9·1 answer
  • Melvin is exploring the different kinds of changes that can happen to substances. After reading about the kinds of changes that
    13·2 answers
  • 14 protons,14 electrons and 14 neutrons
    8·2 answers
  • You discover a new substance that mixes well with H2O initially, but eventually the particles sink to the bottom. What is the BE
    7·1 answer
  • Describe what happens on the molecular level when acetic acid dissolves in water.
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!