Questions and Answers of Chemistry For Engineering Students

Which of the following formulas contains the most hydrogen atoms? C2H6, (NH4)2CO3, H2SO4, or Fe(OH)3.
When talking about the formula of an ionic compound, why do we typically refer to a formula unit rather than a molecule?
Which formula below is correct for an ionic compound? What is incorrect about each of the others?(a) AlO3/2,(b) Ca2Br4,(c) Mg(PO4)3/2, (d) BaCO3
Explain the differences between ionic and metallic bonding.
Explain the difference between a molecular formula and an empirical formula.
Why are empirical formulas preferred for describing polymer molecules?
The molecular formula for the ethylene monomer is C2H4. What is its empirical formula?
Polybutadiene is a synthetic elastomer, or rubber. The corresponding monomer is butadiene, which has the molecular formula C4H6. What is the empirical formula of butadiene?
What distinguished the work of Mendeleev that caused scientists to accept his concept of the periodic table when others before him were not believed?
How does the periodic table help to make the study of chemistry more systematic?
What is a period in the periodic table? From what does it derive its name?
Name the group to which each of the following elements belongs. (a) K, (b) Mg, (c) Ar,(d) Br
What are some of the physical properties that distinguish metals from nonmetals?
A materials engineer has filed for a patent for a new alloy to be used in golf club heads. The composition by mass ranges from 25 to 31% manganese, 6.3 to 7.8% aluminum, 0.65 to 0.85% carbon, and 5.5
Identify the area of the periodic table in which you would expect to find each of the following types of elements.(a) A metal, (b) A nonmetal,(c) A metalloid
Why are nonmetals important even though they account for only a very small fraction of the elements in the periodic table?
What is a metalloid?
Classify the following elements as metals, metalloids, or nonmetals. (a) Si, (b) Zn, (c) B,(d) N, (e) K,(f) S
A materials engineer wants to make a new material by taking pure silicon and replacing some fraction of the silicon atoms with other atoms that have similar chemical properties. Based on the periodic
The chemistry of main group elements is generally simpler than that of transition metals. Why is this so?
Calcium and fluorine combine to produce ionic calcium fluoride, CaF2. Use the periodic table to predict at least two other compounds that you would expect to have structures similar to that of CaF2.
What is meant by the phrase organic chemistry?
The molecule shown below is responsible for the smell of popcorn. Write the correct molecular formula for this compound. N.
What is a functional group? How does the concept of the functional group help to make the study of organic chemistry more systematic?
Not all polymers are formed by simply linking identical monomers together. Polyurethane, for example, can be formed by reacting the two compounds shown below with one another. Write molecular and
The compound shown below forms an amorphous solid (a glass) at room temperature and has been used as a medium for storing information holographically. Write the correct molecular formula for this
The accompanying figure shows the structure of gamma-aminobutanoic acid, or GABA. This molecule is a neurotransmitter. Some of the effects of alcohol consumption are due to the interaction between
The following figure shows the structure of the adrenaline molecule. Write the correct molecular formula for this substance. HO ОН OH H N.
Name the following covalent compounds:(a) N2O5,(b) S2Cl2, (c) NBr3, (d) P4O10
Name the following compounds: (a) PCl5,(b) Na2SO4,(c) Ca3N2, (d) Fe (NO3)3,(e) SO2, (f) Br2O5
What is a free radical? How are free radicals important in the formation of polyethylene?
How do molecules of low-density polyethylene and highdensity polyethylene differ? How do these molecular scale differences explain the differences in the macroscopic properties of these materials?
Why do you think an initiator molecule is needed to induce the polymerization of ethylene?
Use the web to determine the amount of low-density polyethylene and high-density polyethylene produced annually in the United States. Which uses predominate in the applications of these two materials?
LDPE has a density in the range of 0.91520.935 g/cm3, and HDPE has a density in the range of 0.94020.965 g/cm3.You receive a small disk, 2.0 cm high with a 6.0-cm diameter, from a manufacturer of
Use the web to look up the density of different forms of steel, such as stainless steel or magnetic steel, and discuss whether or not the differences in the densities follow what might be predicted

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