CSU Chem 103 Spring 22 Most Missed Questions
Wood is a biofuel and is mostly made of cellulose, a polymer of glucose. Consider the formula of wood to be C12H22O11. How much CO2 is produced when 1.00 kJ of heat is obtained from burning dry wood?
0.075-0.125 g
The lighter fluid used for charcoal grilling is similar to kerosene. How many kilograms of CO2 is emitted when you burn (assume complete combustion) 1.00 kilograms of lighter fluid (C14H30) in your charcoal grill? That's about a liter bottle.
1-10
Biofuels/biomass make up what percentage of renewables? Don't count nuclear as a renewable.
10-25%
If we were to use up the current proved reserves of fossil fuels, how long would they last if the world's energy demands were to stay about what they are today?
100 years
How many atoms are in the first product of the reaction shown in #16 (or above)?
14-16
In 2019 India used 34 EJ of energy. The population of India in 2019 was 1.37 billion people. What is the per capita (per person) energy use for India?
18-27 GJ/person
How many different amino acids are there in naturally occurring proteins?
20
You have a car that runs on hydrogen (H2). The hydrogen tanks in this car can hold 5000 g. How much energy (in MJ) is produced by burning 5000 g of H2?
200-1000
How many atoms are in the molecule on labeled I?
21-27
A cup of gasoline is about 250 mL. When ignited this amount of gasoline explodes into a fireball. (Glass containers around this size are used as grenades in street riots.) If a Snickers bar has 250 kcal when burned. How many Snickers bars equivalents is 250 mL of gasoline? The density of gasoline is 0.75 g/mL (The next time you're in a riot, please throw Snickers bars instead of Molotov cocktails.)
5-10
Draw the Lewis structure for acetylene (C2H2). What is the bond energy for the carbon-carbon bond in acetylene?
813 kJ/mol
Which of the following functional groups is found in the first product of the reaction shown in #16 (or above)?
Amide
What is the monomer that makes up the polymer in wool?
An Amino Acid
Use the bond energy table on the cover page to calculate the energy change associated with the combustion of propane: CH3CH2CH3 + 5 O2 —> 3 CO2 + 4 H2O Notice that the O2 bond is a double bond and the CO bonds in CO2 are double bonds.
Between -4000 and -2000 kJ/mol
The structure of D-glyceraldehyde is shown below: HO__--H Which molecule shown below depicts the mirror image of D-glyceraldehyde?
C) H__--OH
Which of the following is not true concerning bond energies?
Energy is always released when one of the products is water.
Which of the following statements is true about the term "essential" when referring to essential fatty acids?
Humans cannot synthesize these substances so they must be included in the diet.
What is the efficiency of a power plant where the maximum temperature in the furnace is 800 ̊C and the water used for cooling is 20 ̊C?
More than 65%
The bond shown in the triangle is called a(n) ___________ bond.
Peptide
What is shape of the group shown in the rectangle?
Tetrahedral
Which of the following properties of water is not the result of hydrogen bonding?
The molar mass is 18.02 g/mol
Can there be a hydrogen bond between the two groups shown in the oval?
Yes
What is the shape around the atom pointed to by the arrow labeled C?
tetrahedral
What is the shape around the atom pointed to by the arrow labeled E?
tetrahedral