Chemistry 2720 Fall 2000 Assignment 1

Due: Tuesday, Sept. 19, 9:25a.m.

This assignment is intended to help you review material from prerequisite courses useful in our study of thermodynamics. If you find that you have weaknesses in certain areas, you should address them during the first few weeks of classes.

Nomenclature

You are expected to be able to recognize chemical names and transform them to chemical formulas without the assistance of a periodic table, at least for compounds of some of the more common elements. You should know the formulas of several common complex ions. You should also be able to give formulas for some of the common acids. Finally, you are expected to know the formulas of a few common trivially named compounds.

Give chemical formulas for each of the following chemical species. [1 mark each]

1.

sodium hydrogen phosphate

2.

xenon tetrafluoride

3.

iron (III) oxide

4.

cobalt (II) ion

5.

hydrochloric acid

6.

dinitrogen pentoxide

7.

fluorine

8.

calcium bromide

9.

oxygen

10.

ammonia

11.

iodide ion

12.

ammonium nitrate

13.

nickel (II) sulfate hexahydrate

14.

sodium chloride

15.

potassium ion

16.

methane

17.

nitric acid

Balancing chemical reactions

You should be able to balance chemical reactions, whether you are given a complete set of reagents and products or just a verbal description of the reaction.

Balance the following reactions. [3 marks each]

1.

NaCl reacts with SO₂, water and oxygen. The products are Na₂SO₄ and HCl.

2.

Combustion of ethanol ( CH₃CH₂OH)

Basic physical chemistry

You already know a certain amount of basic physical chemistry. Although we will review most of this material as we need it, you are expected to already be familiar with it. You may need to look up a few pieces of data from the textbook to complete the questions in this section. However, you should know the solubility rules well enough to predict which ionic compounds will be soluble in water without reference to a table.

1.

Assuming ideal gas behavior, calculate the number of moles of gas in a $5\,\mathrm{m}\times 5\,\mathrm{m}\times 3\,\mathrm{m}$ room at a pressure of 0.9bar and a temperature of $20^\circ\mathrm{C}$. [5 marks]

2.

Calculate the amount of heat required to raise the temperature of 200g of water from 4 to $20^\circ\mathrm{C}$. [5 marks]

3.

Calculate the amount of heat released when 400g of steam condenses to liquid water at $100^\circ\mathrm{C}$. [4 marks]

4.

Given

Substance	$\Delta\bar{H}^\circ_f$ (kJ/mol)
BCl3(g)	-403.8
BF3(g)	-1136.0
Cl2(g)	0
F2(g)	0

calculate the change in enthalpy ( $\Delta\bar{H}^\circ$) in the reaction $\mathrm{BCl_{3(g)}} + \frac{3}{2}\mathrm{F_{2(g)}} \rightarrow \mathrm{BF_{3(g)}} + \frac{3}{2}\mathrm{Cl_{2(g)}}$. [4 marks]

5.

Relate the equilibrium constant for the reaction $\mathrm{A}+\mathrm{B}\rightarrow\mathrm{C}$ to the concentrations of A, B and C, assuming that the reaction occurs in solution. [2 marks]

6.

Determine the pH of a 0.01mol/L solution of acetic acid in water. [5 marks]

7.

Which of the following ionic compounds are likely to be completely soluble in water? [1 mark each]

(a)

PbSO₄

(b)

Na₂SO₄

(c)

FeS

(d)

(NH₄)₂SO₄

(e)

Pb(NO₃)₂

8.

Which of the following compounds are strong acids in aqueous solution? [1 mark each]

(a)

HF

(b)

H₂SO₄

(c)

H₃PO₄

(d)

HCl

(e)

HSO₄^-

Mathematics

Although the mathematical burden in this course is not particularly heavy, you are expected to be able to work out elementary derivatives and integrals.

1.

Compute the derivative of the function f(x) = 3x⁵+2x+1. [2 marks]  

2.

Compute the following integrals.

(a)

$$\int f(x)\,dx$$ with f(x) as in question 1 [3 marks]

(b)

$$\int_{x_i}^{x_f} dx/x$$ [3 marks]

(c)

$$\int_1^2\frac{3x^2+8x+1}{2x}\,dx$$ [5 marks]