General Chemistry Answers

Butane CH4 at 681°F and 3.00 atm flows into a reactor of 1257 kg/h. Calculate the volumetric flow rate of this stream in m3/min.

 A 4.50 g sample of sugar C5H10O5 (molar mass= 150.0 g/mol) was burned in excess 

oxygen in a bomb calorimeter according to: C5H10O5(s) + 5O2(g) →5CO2(g) +5H2O(l)

If the heat capacity of the calorimeter and its contents was 16.0 kJ/°c, and the 

temperature rose from 25. 0 °C to 26. 5 °C, calculate ΔH in Kj/mol for the combustion 

reaction.

0.4 g sample of hair from a young child is digested in a mixture of HNO, and and diluted to 25 mL. A 10 mL aliquot is diluted to 25 mL and analysed with a ca hollow cathode tube in AAS. The absorbance reading is 0.13. To a second 10 mL is added 1.00 mL of a 0.40 ppm standard cadmium solution, followed by dilution to and analysis for cadmium. The absorbance reading is 0.18. Calculate cadmium con the above hair sample in µg/mL.

1. Calculate the ratio of the rate o effusion of methane gas, CH4 (g) to He (g) at constant temperature and pressure. The molar masses or CH4 (g) and He (g) are 16.0 g/mol and 4.0g/mol, respectively. 
2. Calculate the ratio of the rate of effusion of hydrogen to the rate of effusion of oxygen.
3. At a particular pressure and temperature, nitrogen gas effuses at the rate of 79 mL/s. Using the same apparatus at the same temperature and pressure, at what rate will sulfur dioxide effuse? 
4. Which of the following gases diffuse more slowly than oxygen? F2, Ne, N2O, C2H2, NO, Cl2, H2S

The exothermic reaction of quicklime with water and the rather small specific heats of both

quicklime (0.946 J/g? °C) and slaked lime (1.20 J/g? °C) make it hazardous to store and

transport lime in vessels made of wood. Wooden sailing ships carrying lime would occasionally

catch fire when water leaked into the hold.

(a) If a 500 g sample of water reacts with an equimolar amount of CaO (both at an initial

temperature of 25°C), what is the final temperature of the product, Ca(OH)2? Assume that

the product absorbs all of the heat released in the reaction.

(b) Given that the standard enthalpies of formation of CaO and H2O are 2635.6 kJ/mol and

2285.8 kJ/mol, respectively, calculate the standard enthalpy of formation of Ca(OH)2.

An electrolysis cell for aluminum production operates at 5.0 V and a current of 1.0 x 105 Calculate the number of kilowatt-hours of energy required to produce 1 metric ton (1.0 x 10³ kg) of aluminum

Predict what reaction, if any, will occur when the following species are mixed at standard conditions.

a. Cr, Ni²⁺, Cl^- (in acidic solution)

b.Sulfur is added to mercury.

c.Liquid bromine is added to an aqueous solution of sodium chloride.

Suppose there are 10 liters of a gas at 20 degrees Celsius. If the pressure does not change, what will be the volume of the gas at O degree Celsius

Consider a salt bridge voltaic cell represented by the following reaction:

Fe(s) + Tl⁺(aq) ------> Fe²⁺(aq) + 2Tl(s)

Choose the best answer from the choices in each part below:

a. What is the path of electron flow? Through the salt bridge, or

through the external circuit?

b. To which half-cell do the negative ions in the salt bridge move? Themanode, or the cathode?

c. Which metal is the electrode in the anode?

2Fe + 3Cl2 = 2FeCl3