Answer:
The mesosphere is 22 miles (35 kilometers) thick. ... Those meteors are burning up in the mesosphere. The meteors make it through the exosphere and thermosphere without much trouble because those layers don't have much air. But when they hit the mesosphere, there are enough gases to cause friction and create heat.
To determine the mass of the sample in milligrams in this problem, we use the avogadro's number to convert from atoms to moles, relate the moles of element in the sample to the mole present and the molar mass of the sample. We do as follows:
1.552 x 10^22 atoms H ( 1 mol H / 6.022x10^23 atoms H ) ( 1 mol C2H4Cl2 / 4 mol H ) ( 98.96 g C2H4Cl2 / 1 mol C2H4Cl2 ) = 0.625 g C2H4Cl2 = 625 mg <span>C2H4Cl2</span>
<u>Answer:</u> of the reaction will be negative, of the reaction will be positive and of the reaction will be negative.
<u>Explanation:</u>
Thermodynamic properties are enthalpy change , entropy change and Gibbs free energy
Exothermic reactions are defined as the reactions in which energy is released in the form of heat. The enthalpy change of the reaction comes out to be negative for this kind of reaction.
Entropy change is defined as the change in the measure of randomness in the reaction. It is represented as . Randomness of gaseous particles is more than that of liquid which is further more than that of solids.
For the given exothermic reaction:
As, number of gaseous particles on the product side is more than the number of gaseous particles on the reactant side. So, the entropy change is positive. Hence, is positive.
The above reaction is spontaneous. Thus, the Gibbs free energy will be negative.
For the given reaction:
Answer:
6.5
Step-by-step explanation:
We know we will need a balanced equation with masses and molar masses, so let’s gather all the information in one place.
M_r: 187.56 18.02
Cu(NO₃)₂·nH₂O ⟶ Cu(NO₃)₂ + nH₂O
m/g: 7.0 4.3
1. <em>Moles of Cu(NO₃)₂
</em>
Moles of Cu(NO₃)₂ = 4.3 g × (1 mol/187.56 g)
Moles of Cu(NO₃)₂ = 0.0229 mol
2. <em>Mass of H₂O
</em>
Mass of Cu(NO₃)₂·nH₂O = mass of Cu(NO₃)₂ + mass of H₂O
7.0 = 4.3 + x
7.0 - 4.3 = x
2.7 = x
3. <em>Moles of H₂O
</em>
Moles of H₂O = 2.7 g × (1 mol/18.02 g)
Moles of H₂O = 0.150 mol
4. <em>Value of n
</em>
The molar ratio is 1 mol (NO₃)₂ = n mol H₂O
n = moles H₂O/moles Cu(NO₃)2
n = 0.150/0.0229
n = 6.5
This answer does not make sense, because the maximum value of n in hydrated copper(II) nitrate is 6.
Answer:
North American X-15
Explanation:
This is the fastest manned aircraft