<span>The enthalpy of an intermediate step when used to produce an overall chemical equation should be manipulated in this way:
</span><span>Multiply the enthalpy by –1 if the chemical equation is reversed.
If the forward reaction requires energy, the reverse will produce energy.</span>
Answer:
269.068 kJ/mol.
Explanation:
<em>ln (k₂/k₁) = (Eₐ/R) [(T₂ - T₁)/(T₁T₂)].</em>
<em>k₁ = 6.20 x 10⁻⁴ min⁻¹, T₁ = 700.0 K.</em>
<u><em>To get k₂:</em></u>
in first order reactions: k = 0.693/(half-life).
∴ k₂ = 0.693/(29.0 min) = 2.39 x 10⁻² min⁻¹, T₂ = 760.0 K.
∵ ln (k₂/k₁) = (Eₐ/R) [(T₂ - T₁)/(T₁T₂)]
∴ ln [(2.39 x 10⁻² min⁻¹)/(6.20 x 10⁻⁴ min⁻¹)] = (Eₐ/(8.314 J/mol.K)) [(760.0 K - 700.0 K) / (760.0 K)(700.0 K)].
3.65 = (Eₐ/(8.314 J/mol.K)) (1.128 x 10⁻⁴).
<em>∴ Eₐ =</em> (3.65)(8.314 J/mol.K) / (1.128 x 10⁻⁴) = <em>269.068 kJ/mol.</em>
Explanation:
Question 1:
It is better to use data from three or more seismic stations to find the epicenter of an earthquake because it gives a precise and accurate location better than using a lesser amount of data.
Finding epicenter of an earthquake works on the basis of triangulation.
- The intersection between three circles gives the epicenter.
- To triangulate, we simply use a radius value to draw a circle of appropriate size.
- This is the distance of the station from the earthquake.
- We know using seismograph that the first wave to arrive a point is the p-waves and the s-waves follows.
- Disparity between the time of arrival and the velocity of the wave can give us the distance the wave must have traveled.
- We take this data and draw circle of appropriate radius indicating the probable regions where the epicenter might be located.
- This is a wide and indefinite volume of space.
- Three circles using data from two more stations will give a perfect intersection.
- More stations will further improve the accuracy and then we are sure of where the epicenter is.
learn more:
Epicenter brainly.com/question/11292835
Question 2:
P and S-waves are seismic elastic waves that travels within the earth. They are usually produce when a huge vibration travels within a substance or within the earth.
After the passing of the wave, the body returns back to its original form.
P-waves:
- They are called primary waves.
- They have the fastest velocity and the are the first to be picked up at a seismic station.
- They can propagated through any material.
- These waves are longitudinal waves moving in a series of rarefaction and compression.
S-waves:
- They are secondary or shear-waves.
- They are the second to arrive seismic station.
- They cannot pass through fluids because they do not shear.
- They are transverse waves that travels perpendicular to their source.
learn more:
Earthquake brainly.com/question/6520403
Question 3:
If a seismogram from a particular seismic station shows only P-waves, one can conclude that the material is only made up of fluid materials.
- P-waves are primary waves capable of moving in any material medium.
- They are longitudinal waves that propagates parallel to their source.
- The reason why we cannot pick other seismic waves is that, s-waves cannot pass through fluids.
- S-waves are secondary or shear waves.
- Fluids cannot be sheared.
- Only solids can shear.
- Therefore, we can imply that since we see only p-waves the material is made up of only fluids.
learn more:
Seismic brainly.com/question/6520403
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Answer: 878 kJ of energy is there in cheeseburger
Explanation:
Given : calorific value of fat = 38kJ/g
calorific value of carbohydrate = 17 kJ/g
calorific value of protein = 17kJ/g
1 g of fat contains energy = 38 kJ
7.0 g of fat contains energy =
1 g of carbohydrate contains energy = 17 kJ
25 g of fat contains energy =
1 g of protein contains energy = 17 kJ
11 g of protein contains energy =
Total energy = (266+425+187) kJ = 878 kJ
Answer:
(a). 4
(b). 1 triple bond.
(c). 1
(d). 1 ring.
Explanation:
Without mincing words let's get started. So, we have that the chemical formula for the compound is C8H10. So, we are given from the question that lindlar's catalysts which is represented by H2 / Pd / CaCO3 and used in hydrogenation especially from alkyne to alkene.
(a). The degrees of unsaturation in the unknown can be calculated as;
[ (2 × Number of carbon atoms) + (2 ) - (number of Nitrogen atoms) - (number of hydrogen atoms) - number of halogens) ÷ 2
= [(2 × 8) + 2 - 0 - 10 - 0 ] ÷ 2.
=( 16 + 2 -10 ) ÷ 2.
= ( 18 - 10) ÷ 2 = 8/2 = 4.
(b). The number of triple bonds is 1 because we are given from the question that "On catalytic hydrogenation over the Lindlar catalyst, 1 equivalent of hydrogen is absorbed" and this is the work of the catalyst to prevent the alkyne from going to alkane straight.
(c). The number of double bonds is 1 because we are given from the question that "On hydrogenation over a palladium catalyst, 3 equivalents of H2 are absorbed".
(d)The number of rings is 1