Avery

If the heat of combustion for a specific compound is -1340.0 kJ/mol and its molar mass is 67.97 g/mol, how many grams of this compound must you burn to release 942.60 kJ of heat?

A 0.6410-kg ice cube at -12.40°C is placed inside a chamber of steam at 365.0°C. Later, you notice that the ice cube has completely melted into a puddle of water. If the chamber initially contained 6.190 moles of steam (water) molecules before the ice is added, calculate the final temperature of the puddle once it settled to equilibrium. (Assume the chamber walls are sufficiently flexible to allow the system to remain isobaric and consider thermal losses/gains from the chamber walls as negligible.)

(1) Find the linear approximation of f (x) = sqrt(x) at x = 9.

(2) use your answer from part 1 to estimate sqrt(9.3).

If 402 mol of octane combusts, what volume of carbon dioxide is produced at 20.0 °C and 0.995 atm?

The combustion of octane, C8H18, proceeds according to the reaction

2C8H18(l)+25O2(g) --> 16CO2(g) + 18H2O(l)

Chlorine can be prepared in the laboratory by the reaction of manganese dioxide with hydrochloric acid, HCl(aq), as described by the chemical equation

MnO2(s) + 4HCl(aq) --> MnCl(aq) + 2H2O(l) +Cl2(g)

How much MnO2(s) should be added to excess HCl(aq) to obtain 165 mL of Cl2(g) at 25 degrees celsius and 765 Torr??

In the following reaction, how many liters of oxygen, O2, measured at STP, would be produced from the decomposition of 237 g of potassium chlorate, KClO3?

2KClO3(s) ----> 2KCl(s)+3O2(g)

A 9.30-L container holds a mixture of two gases at 25 °C. The partial pressures of gas A and gas B, respectively, are 0.175 atm and 0.688 atm. If 0.190 mol of a third gas is added with no change in volume or temperature, what will the total pressure become?

The organic compound di-n-butyl phthalate, C16H22O4(l), is sometimes used as a low-density (1.046 g·mL^–1) manometer fluid. Compute the pressure (in torr) of a gas that supports a 641-mm column of di-n-butyl phthalate. The density of mercury is 13.53 g·mL^–1.

I dont really know how to do this so if you could explain how you got it that would help a ton!! thanks!!

If the heat of combustion for a specific compound is -1310.0 kJ/mol and its molar mass is 29.37 g/mol, how many grams of this compound must you burn to release 250.70 kJ of heat?

A motor transforms 51.2 J of electrical energy into work by turning a drum which in turn winds up a cord and raises a mass up off of the ground. Express the quantity of work that was done in calories.

Give the answer as a multiple of pi. Do not use decimal numbers. The answer should be a fraction or an integer. Note that pi is already included in the answer so you just have to enter the appropriate multiple. E.g. if the answer is pi/2 you should enter 1/2. If there is more than one answer enter them separated by commas.

(cos(t))^2=(3/4)