Answer:The structure of solids can be described as if they were three-dimensional analogs of a piece of wallpaper. Wallpaper has a regular repeating design that extends from one edge to the other. Crystals have a similar repeating design, but in this case the design extends in three dimensions from one edge of the solid to the other.
We can unambiguously describe a piece of wallpaper by specifying the size, shape, and contents of the simplest repeating unit in the design. We can describe a three-dimensional crystal by specifying the size, shape, and contents of the simplest repeating unit and the way these repeating units stack to form the crystal.
The simplest repeating unit in a crystal is called a unit cell. Each unit cell is defined in terms of lattice points--the points in space about which the particles are free to vibrate in a crystal.
Answer:
Wavelength is 10m
Explanation:
To solve this problem, we use the formula for wavelength
Wavelength = wave velocity / frequency
Wavelength = 50m/s / 5Hz
= 10m
Answer
is: activation energy of this reaction is 212,01975 kJ/mol.<span>
Arrhenius equation: ln(k</span>₁/k₂) =
Ea/R (1/T₂ - 1/T₁).<span>
k</span>₁
= 0,000643 1/s.<span>
k</span>₂
= 0,00828 1/s.
T₁ = 622 K.
T₂ = 666 K.
R = 8,3145 J/Kmol.
<span>
1/T</span>₁ =
1/622 K = 0,0016 1/K.<span>
1/T</span>₂ =
1/666 K = 0,0015 1/K.<span>
ln(0,000643/0,00828) = Ea/8,3145 J/Kmol ·
(-0,0001 1/K).
-2,55 = Ea/8,3145 J/Kmol </span>· (-0,0001 1/K).<span>
Ea = 212019,75 J/mol = 212,01975 kJ/mol.</span>
0,35 kmol/m³ = 0,35 mol/dm³ = 0,35 mol/L
175 mL = 0,175 L
*-*-*-*-*-*-*-*-*-*-*-*
C = n/V
n = 0,35×0,175
n = 0,06125 mol
mCa(NO₃)₂: 40+(14×2)+(16×6) = 164 g/mol
1 mol --------- 164g
0,06125 ---- X
X = 10,045g
To prepare 175 mL of 0,35M solution, add 10,045g of calcium nitrate and add water to a volume of 175ml.
The equations of reaction occurring in the tubes are as follows:
- 2 MnO₄⁻ + 6 Br⁻ + 8 H⁺ → 2 MnO₂ + 3 Br₂ + 4 H₂O
- 2 MnO₄⁻ + 6 I⁻ + 8 H⁺ → 2 MnO₂ + 3 I₂ + 4 H₂O
- No reaction
- 2 Fe³⁺ + 2 I⁻ → 2 Fe²⁺ + I₂
<h3>What are the reactions occurring in the tubes?</h3>
The reactions occurring in the tubes are redox reactions.
Based on the table the equations of reaction are as follows:
- 2 MnO₄⁻ + 6 Br⁻ + 8 H⁺ → 2 MnO₂ + 3 Br₂ + 4 H₂O
- 2 MnO₄⁻ + 6 I⁻ + 8 H⁺ → 2 MnO₂ + 3 I₂ + 4 H₂O
- No reaction
- 2 Fe³⁺ + 2 I⁻ → 2 Fe²⁺ + I₂
In conclusion, redox reaction are reactions in which electrons are transferred.
Learn more about redox reactions at: brainly.com/question/26750732
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