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The atmosphere protects us from all of the following except Meteorites The sun's rays Pollution Wind

denis23 [38]

Meteorites is the answer

6 0

3 years ago

Label the sound wave- amplitude, wavelength, crest, trough

enot [183]

Answer:

A - Crest, B - amplitude, C - wavelength, D - trough

Explanation:

7 0

2 years ago

Arrange the following substances in order of decreasing magnitude of lattice energy.

kolbaska11 [484]

The formula is F = ( q1 * q2 ) / r ^ 2
where: q is the individual charges of each ion 
r is the distance between the nuclei 
The formula is not important but to explain the relationship between the atoms in the compounds and their lattice energy. 

From the formula we can first conclude that compounds of ions with greater charges will have a greater lattice energy. This is a direct relationship. 
For example, the compounds BaO and SrO, whose ions' charges are ( + 2 ) and ( - 2 ) respectively for each, will have greater lattice energies that the compounds NaF and KCl, whose ions' charges are ( + 1 ) and ( - 1 ) respectively for each. 

So Far: ( BaO and SrO ) > ( NaF and KCl ) 

The second part required you find the relative distance between the atoms of the compounds. Really, the lattice energy is stronger with smaller atoms, an indirect relationship. 
For example, in NaF the ions are smaller than the ions in KCl so it has a greater lattice energy. Because Sr is smaller than Ba, SrO has a greater lattice energy than BaO. 

Therefore: 
Answer: SrO > BaO > NaF > KCl

5 0

3 years ago

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An oil slick on water is 120 nm thick and illuminated by white light incident perpendicular to its surface. What color does the

gregori [183]

Answer:

$\lambda = 672 nm$

so this is nearly red colour light

Explanation:

As we know that the interference of light from reflected light then the path difference is given as

$\Delta x = 2\mu t + \frac{\lambda}{2}$

now we know that for constructive interference of light the path difference is given as

$\Delta x = n\lambda$

so we will have

$2\mu t + \frac{\lambda}{2} = N\lambda$

so we will have

$4\mu t = \lambda$

$\lambda = 2(1.40)(120nm)$

$\lambda = 672 nm$

so this is nearly red colour light

8 0

3 years ago

Mount Everest rises to a height of 8,850 m above sea level. At a base camp on the mountain the atmospheric pressure is measured

Mamont248 [21]

Answer:

74.86°C

Explanation:

P₂ = Vapour pressure of water at sea level = 760 mmHg

P₁ = Pressure at base camp = 296 mmHg

T₂ = Temperature of water = 373 K

ΔH°vap for H2O = 40.7 kJ/mol = 40700 J/mol

R = Gas constant = 8.314 J/mol K

From Claussius Clapeyron equation

$ln\frac{P_2}{P_1}=\frac{\Delta H}{R}\left(\frac{1}{T_1}-\frac{1}{T_2}\right)\\\Rightarrow ln\frac{760}{296}=\frac{40700}{8.314}\left(\frac{1}{T_1}-\frac{1}{373}\right)\\\Rightarrow ln\frac{760}{296}\times \frac{8.314}{40700}+\frac{1}{373}=\frac{1}{T_1}\\\Rightarrow 0.0028735=\frac{1}{T_1}\\\Rightarrow T_1=347.996\ K$

T₁ = 347.996 K = 74.86°C

∴Water will boil at 74.86°C

4 0

3 years ago