Chemistry for Engineering Students 1th. Edition by Larry Brown, Tom Holme | 9780534389741 | 0534389740

General Chemistry

Chemistry for Engineering Students

122 SOLVED PROBLEMS

1 SOLVED PROBLEMS

Question: 13.EP.1

Copper and iron (generally in the form of steel) are two of the many metals used in designing machines. (a) Using standard reduction potentials, identify the anode and the cathode, and determine the cell potential for a galvanic cell composed of copper and iron. Assume standard conditions. (b) We ...

Verified Answer:

(a) Using Table 13.1, we find the following two ha...

Question: 3.EP.7

A demolition engineer is planning to use the explosive ethylenedinitramine (C2H6N4O4, also known as halite) to bring down an abandoned building.Calculations show that 315 moles of the compound will provide the necessary explosive force.How many pounds of C2H6N4O4 should be used? ...

Verified Answer:

We will need to calculate the molar mass of the co...

Question: 3.EP.5

Determine the molar mass of each of the following compounds, all of which have been used as explosives: (a) lead azide, PbN6, (b) nitroglycerin, C3H5N3O9, (c) mercury fulminate, Hg(ONC)2 ...

Verified Answer:

\begin{matrix}(a) \ PbN_{6}: & & 1...

Question: 3.EP.6

A sample of the explosive TNT (C7H5N3O6) has a mass of 650.5 g.How many moles of TNT are in this sample? How many molecules is this? ...

Verified Answer:

First we will calculate the molar mass of TNT. [la...

Question: 13.EP.2

Suppose that you work for a company that designs the drive mechanisms for large ships. The materials in this mechanism will obviously come into contact with environments that enhance corrosion. To estimate the difficulties that corrosion might cause, you decide to build a model electrochemical cell ...

Verified Answer:

Anode reaction:

Fe^{2+}(aq) + ...

Question: 12.EP.15

The conversion of methane gas (CH4) to methanol (CH3OH), which is a liquid at room temperature, is an area in which considerable research is being done. Still, this process is not yet economically viable. Using tabulated thermodynamic data, calculate the equilibrium constant for the following ...

Verified Answer:

ΔG° = ΔG_{f}°[CH_{3}OH(l)] −\left\{ ΔG_{f}°...

Question: 12.EP.12

The Ksp of Ca3(PO4)2 is 2.0 × 10^−33. Determine its molar solubility in 0.10 M (NH4)3PO4. Compare your answer to the molar solubility of Ca3(PO4)2 in water, which we calculated in Example Problem 12.11. ...

Verified Answer:

Let x = moles of

Ca_{3}(PO_{4})_{2}

...

Question: 12.EP.6

When hydrogen gas reacts with iodine gas at elevated temperatures, the following equilibrium is established: H2(g) + I2(g) ⇄ 2 HI(g) A student measured the equilibrium constant as 59.3 at 400°C. If one trial begins with a mixture that includes 0.050 M hydrogen and 0.050 M iodine, what will be the ...

Verified Answer:

Because only

H_{2}

and

I_{2}...

Question: 12.EP.3

In Example Problem 12.2, we saw that cyanide ions precipitate with silver. Bromide ions show similar behavior. The two pertinent equilibria are Ag^+(aq) + CN^−(aq) ⇄ AgCN(s) K = 1.7 × 10^16 Ag^+(aq) + Br^−(aq) ⇄ AgBr(s) K = 1.9 × 10^12 Which ion is more likely to precipitate silver from a solution, ...

Verified Answer:

Both equilibrium constants are much greater than o...

Question: 12.EP.2

Cyanide ions will precipitate from a solution that also contains silver ions, as described by the following equilibrium: Ag^+(aq) + CN^-(aq) ⇄ AgCN(s) Write the equilibrium expression for this reaction. ...

Verified Answer:

K=\frac{1}{[Ag^{+}][CN^{-}]}

Analyz...

Question: 5.F.1

A balloon is to be used to float instruments for observation into the upper atmosphere. At sea level, this balloon occupies a volume of 95 L at a temperature of 20°C. If helium gas is used to fill the balloon, how would you determine the maximum height that this balloon and its instruments will ...

Verified Answer:

First identify what is known about the variables i...