Civil and Environmental Engineering Answers

I. What are the possible risks of using chemicals?

II. How can you protect yourself from hazardous chemicals?

III. What are you going to do if you inhaled hazardous chemicals?

IV. How can you protect the environment from chemical hazards?

Calculate the specific volume, entraphy and specific internal energy of wet steam at 18 bar, dryness fraction 0.9

The standard heat of combustion of liquid benzene (giving liquid water) is -41.88 kJ/g at 25°C. The heats of formation of carbon dioxide and water vapor are -393.51 and -241.82 kJ/mol, respectively, at 25°C and one bar pressure. Calculate the enthalpy change for the formation of benzene (C6H6) from the elements at 25°C and one bar.

Find, approximately, the amount of metal in a closed tin can 3 inches in diameter and 5 inches

high, if the metal is 1/32 inches thick.

Find, approximately, the amount of metal in a closed tin can 3 inches in diameter and 5 inches high, if the metal is 1/32 inches thick.

Find by use of differentials the approximate total area of a right circular cone whose base radius and height are 5.03 inches and 11.89 inches, respectively.

Station of the PI of the curve: 7+400

Elevation of

L1 =

L2 =

G1 = G2 =

the PI of the curve: 80m.

  160m

  120m

  +7%

  -4%

a) Determine

starting from PC to PT. Tabulate your answer and show solutions.

Find by use of differentials the approximate total area of a right circular cone whose base radius and height are 5.03 inches and 11.89 inches, respectively.

A bridge 10-m wide is to be placed across a proposed underpass. This underpass is designed to have a grade of -4% and an ascending grade of +8%, where its vertex will be located at 4+420 with an elevation of 140m. It is required that the centerline of the bridge is exactly placed above the vertex of the curve, its bottom elevation is 148.10m and it should have a minimum vertical clearance of 6m under it.

a) Determine the length of the vertical parabolic curve.

b) Determine the location of the lowest point of the

curve.

c) Determine the elevation of the lowest point.

d) Determine the stationing and elevation of PC.

e) Determine the stationing and elevation of PT.

Find the increment and differential of each of the following functions for the given values of the

variables and their increments.

𝑦 tan^-1 𝑥𝑦; 𝑥 = 2, 𝑦 = 0.5, ∆𝑥 = −0.05, ∆𝑦 = 0.01