1.3A(g) + X(g) → Z(g) ΔH° = -480 kJ/molrxn
The equation shown above represents an exothermic reaction between A(g)
reaction between A(g) and X(g). What is the amount of heat released when 10 mol of A(g) reacts with an excess X(g) ?
Using the heats of formation found in the table above, calculate ΔH for the reaction below.
6A(aq) + 7X(g) → 6Y(l)
Y + 2X → 4Z ΔH=-4
A + 3B → 2Z ΔH=-2
A → X +C ΔH=7
Using the thermodynamic data above, determine ΔH for the reaction below.
2C+ 6B → Y
When 0.3 moles of A(s) (4 grams) is dissolved in 12 grams of water at 23°C, the temperature of the water increases to 31°C. The specific heat of water is 4.18 J/g°C.
Calculate ΔH in kJ/mol. Report your answer to 1 decimal place.
2.I am trying to figure out the optimal radius that will give the lowest surface area of a cylinder. I
have done the calculus which reveals that the surface area is at a minimum when height is double the radius. I am now trying to find an equation for the relationship between the amount of wasted surface area as a percentage of the minimum surface area and the ratio between height and radius.
If I were to plot it on a graph, the y axis would be the percentage of excess materials needed as a percentage of the minimum possible surface area, and the x axis would be height divided by radius. Since the surface area is minimized when height=2(radius), I know that when x=2, y=0.
The website https://www.datagenetics.com/blog/august12014/index.html explains what I am trying to do quite well and shows the graph below. I am trying to find the equation for this graph, but am unsure how to go about it.
4.So I am looking at polar and Cartesian and converting between the two. My question is, I have never seen
seen an equation of a circle this is moved in both the x and y direction be converted to a polar equation.
For example, I know that the equation of a circle x^(2)+(y-2)^(2)=4 is r=4sin(theta) when converted to polar. Same thing for a translation with the x variable. However, I have never seen, nor do I know how to do, a conversion of a circle with both translations. For example, converting this equation of a circle to a polar equation: (x+3)^(2)+(y-4)^(2)=4. I have no idea how to do such a thing and cannot find any examples of such.
Hope you can shed some light on this, Thanks.