Chapter 6 Review Questions Flashcards
The combustion of coal releases several substances into the air.
A) of these substances, one is a gas that is produced in large amounts. Give it’s chemical formula and name
B) in contrast, the amount of SO2 (sulfur dioxide) released is relatively small. Even so, this SO2 is of concern, explain why.
A) CO2, carbon dioxide
B) SO2, is an air pollutant. Although sulfur is present in low concentrations in coal, large amounts of coal are burned, and collectively large amounts of SO2 are released
C) another gas produced in small amounts is NO (nitrogen monoxide). However, cola contains very little nitrogen. What is the origin of the nitrogen in NO?
D) when coal burns, fine particles of soot may be released. What are the health concerns with PM 2.5, the smallest of these particles?
C) nitogren is present in the air ( around 80% of atmospheric gases). The nitrogen present in air reacts with O2 (also N2 + O2 ——- (high temperature)—> 2NO present in the air) at high temperatures to form NO
D) long term exposure has been proven to be damaging to the body. Long term and short term effects have both been proven to affect the human body and they both can lead to heart and lung problems or even reduce lung function over time of having may exposures.
Chemical compound, formulas of pentane, C5H12 (Melting point @ -130.5, boiling point @ 35.9) formula of triacontane, C30H62 (melting point @ 65.8, boiling point @ 449.7) formula of propane, C3H8 (melting point @ - 187.7, boiling point @ -42.2)
At room temperature (25 C), categorize each one as a solid, liquid or gas
Pentane: a liquid
Triacontane: a solid
Propane: a gas
Write the balanced equation for the complete combustion of n-heptane, C7H16
C7H16 + 11 O2 ——-> 7 CO2 + 8 H2O
State whether these processes are endothermic or exothermic
A) charcoal burns in an outdoor grill
B) water evaporates from your skin
C) glucose is synthesize in the leave of a plant by photosynthesis
A) exothermic
B) endothermic
C) endothermic
A) Is ethane an isomer of ethene? Of ethanol? Explain
B) are any other isomers possible for ethene? Explain
C) are there any other isomers possible for ethanol? Explain
A) none of thse are isomers, all have different chemical formulas
B) no, no other isomers are possible for ethene
C) one other isomer is possible, although it contains a very distinct functional group, called an ether…. It’s condensed structural formula is CH3 - O - CH3
When glucose, C6H12O6, is “burned” (metabolized) in your body, the products are carbon dioxide in water.
A) write the balanced chemical equation
B) the chemical equation for burning wood is essentially the same as that of metabolizing glucose. Explain why
A) C6H12O6 + 6 O2 —> 6 CO2 + 6 H20 + energy
B) cellulose is one of th primary components of wood. Cellulose is a polymer made up of glucose building blocks. As a result, burning cellulose gives products comparable of burning glucose
Why are chlorofluorocarbons (CFCs) are so stable? Also explain why it takes less energy to release Cl atoms from CFC’s than it does to release F atoms and connect this to HFCs as replacements for CFCs.
CFC’s are stable because the bond energies for C-Cl and C-F are large compared to other bond energies. It takes less energy to release Cl atoms from CFCs because the C-Cl bond energy (327 kJ/mol) is lower than the C-F bond energy (485 kjj/mol). HFCs, with their C-F bonds and (no C-Cl bonds), release no Cl atoms
