<--CHM130 Home/Progress Page

There are three times available for taking the on-campus final in a classroom C329, which is Building C (SE corner of campus) on 3rd floor.  Thursday, May 2nd, 7-9pm, Tuesday, May 7th 7-9pm, and Thurs. May 9th 7-9pm. The test will also be in the Testing Center for students who can't make these times; however, you need to make arrangements with their instructor first because the Testing Center has to have your name on a list and have your test on file. If you are in Mr. Costello's class (section 20752), email him at chm130@chemistryland.com to request to take test in the Testing Center. If you are in Mr. Thacker's class (section 22493), email him at qrt2004@yahoo.com.  If you can't come to the campus, contact your instructor for special arrangements.  An over-the-phone final may be done instead.

Below is a the practice exam for the CHM130 on-campus final exam.

Answer: It contains toxic mercury and the glass could break.

Are the values on this thermometer in Fahrenheit or Celsius?

The left thermometer is reading 37.0°C. What is that in Fahrenheit?

The right thermometer is reading 98.6°F. What is that in Celsius?

(37.0°C x 9/5) + 32 = 98.6°F

(98.6°F-32) x 5/9 = 37.0°C

What sensor in the left thermometer is responsible for detecting the temperature and name one of its ingredients?
Answer: A thermistor. (Remember one of the following:) manganese oxide, cobalt oxide, nickel oxide or copper oxide

What sensor in the ear thermometer is responsible for detecting temperature?
Answer: A thermopile (or array of thermocouples).

Name one metal that is used to make a thermocouple.
Answer: (Remember one of these metals): chromium, nickel, copper, tungsten, or platinum.

What is the name of this device?

What is this person's SpO2% reading?

What does SpO2% stand for?
Answer: Percent (%) that hemoglobin is saturated (S) with oxygen (O2) in a peripheral (p) part of the body (for example, fingers).

What is this person's pulse (heart rate)?

Below what percent should a person get worried?

Here is a wrist band for taking blood pressure measurements. What is the systolic (high) blood pressure?

What is the diastolic pressure?

What does "mmHg" stand for?

What is this person's pulse rate?

Is this blood pressure monitor manual or automatic?
Answer: It's automatic because there's a Start/Stop button

Can this device store blood pressure readings?

What do the numbers 120, 80, and 73 represent?
Answer: 120 is the systolic pressure. 80 is the diastolic pressure. 73 is the pulse rate.

Hypertension is another term for high blood pressure. What systolic and diastolic pressures are considered hypertension? (Note: these are values when a person is at rest).
Answer: 140 and above for systolic pressure. 90 and above for diastolic pressure.

Extra credit: What pressures are considered an emergency situation?
Answer: 180 or more for systolic pressure. 110 or higher for the diastolic pressure.

These blood pressure readings are in millimeters of mercury (mmHg). 760 mmHg is the same as 14.7 pounds per square inch (psi). A pressure of 180 mmHg has how many pounds per square inch on the blood vessels and heart?
180mmHg x 14.7psi= 3.5 lbs per square inch.
760mmHg

(So in just a 2 inch by 2 inch section of the heart, the heart is feeling the weight of a bowling ball (14 lbs). You can understand why high blood pressure is something not to ignore.)

To the left is a blood glucose meter and strip. What is the blood sugar level?

That level is measured in mg/dL. What does mg/dL stand for?

How many milliliters is one deciliter?

The amount of blood needed to do a test is 1 microliter.  If the reading is 105 mg/dL, how many mg of glucose did the glucose meter use?

Answer: 1 microliter means 1 millionth of a liter. Multiply by 1000 for 1000 tests.
1 liter   x 105 mg x deci = 0.00105 mg glucose
1,000,000    1 dL     0.1

Notice liter and deci cancel.  0.00105 mg is a very small quantity.  These glucose meters are quite sophisticated little machines.

The amount of blood needed to do a test is 1 microliter. If 1000 tests were run, how much blood would be needed?
Answer: 1 microliter means 1 millionth of a liter. Multiply by 1000 for 1000 tests.
1 Liter  x 1000=   1  Liter
1,000,000         1000

1/1000 liter is the same as 1 milliliter.

A glucose meter uses the enzyme called glucose oxidase. What does the "ase" mean?
Answer: The "-ase" suffix is usually added to indicate this is an enzyme (a protein that speeds up a chemical reaction).

What does the "oxi" in oxidase indicate?
Answer: "Oxi" usually refers to oxygen. It means that it either adds oxygen atoms or it behaves like oxygen, which is to strip electrons away from things.

What does the A1C test for?
Answer: It determines the average blood sugar level over the last 2 to 3 months. The reading is the percent of the hemoglobin in red blood cells that are coated with sugar (glucose).

The reading in the photo says 6.3 %A1C. What does that mean?
Answer: It means 6.3% of the hemoglobin proteins in the red blood cells are permanently coated with glucose (sugar).

Is the reading of 6.3% high or low?
Answer: It's a little high because 4.0% to 6.0% is normal.

At what reading is a person considered diabetic?

A person can get urine test strips for home use. They are fairly inexpensive.
The strips in the top image have 10 squares. That means that could test for 10 different substances in the urine.

The below chart is from a urine test strip that measures the concentration of five different substances.

The highest level for glucose says >110 mmol/L.    What does mmol/L stand for?

The pH range goes from 5.0 to 8.5. Is pH 5 acidic or alkaline?  What about pH 8.5?
Answer: pH 5 is acidic. Anything under 7.0 is acidic. 8.5 would be alkaline urine.

The units for protein in the urine are often written as 1+, 2+, 3+, 4+.  1+ means 30mg/dL. 2+ means 100mg/dL, and 3+ means 300mg/dL. What does mg/dL stand for?
Answer: milligrams per deciliter (or milligrams per 100mL).

If a person has a high reading for ketones, their urine (and breath) is likely to smell like what?

A high level of glucose in the urine indicates what condition?

In the terms proteinuria, ketonuria, and hematuria, what does "uria" mean?
Answer: That means in urine or related to urine.

What does hematuria mean?
Answer: It means there is blood in the urine.

The home pregnancy test will measure the presence of the hormone called human chorionic gonadotropin. What abbreviation is used for this hormone?

Does a colored band at the T region indicate a positive or negative for pregnancy?
Answer: A band at the T region is positive indication of the hormone and therefore indicates the one tested is pregnant.

A band that shows up at the C region means what?
Answer: It means the test is complete and one should then look to see if a band is at the T region.

Hormones, enzymes, and anti-bodies belong to what class of organic compounds?
Answer: They are all proteins, which are chains of amino acids.

Sometimes "globulin" is written after an enzyme name. What does "globulin" mean?
Answer: It means that protein is globular or globe-like in shape.

This multi-test strip tests for 5 different drugs in the urine. What do the code letters, COC, AMP, THC, OPI, and PCP stand for?
Answer: Cocaine, amphetamine, THC (marijuana), opiates like opium, morphine and heroin, and PCP.

Extra credit. What does THC and PCP stand for?
THC is tetrahydrocannabinol, which is the psychoactive chemical in the cannabis plant (marijuana). PCP is phencyclidine.
PCP comes from letters in the full chemical name, which is phenylcyclohexylpiperidine.

Unlike the pregnancy test, a band of color showing up at the T region on a drug test indicates what?
Answer: A negative. No drug found.

If no color band shows up at the "T" label, what does that mean?
Answer: A positive. The drug is present. Note: If drug is present, it prevents a band of color from showing up at the T region.

In these kinds of tests, what type of protein is used to identify a particular drug?

This is the saliva version of the urine drug test. This one tests for one extra drug because it has the letters "mAMP". What drug is that referring to?

Amphetamine is an shortened version of the full chemical name. Here is the full chemical name with certain letters highlighted in red. What do those letters spell?
alpha-methylphenethylamine.

What is an "amine" group?
Answer:  Amines are based on ammonia (NH3) where one or more of the hydrogen atoms are substituted for a carbon atom attached to other atoms.  (For example, CH3-NH2 is methylamine.)

The word "methyl" or "meth" indicates a CH3 group. So what do you think is the difference between amphetamine and methamphetamine?
Answer: Methamphetamine is the same as amphetamine but methamphetamine has an extra methyl group on it.

Here is a breathalyzer that uses a fuel cell for the alcohol sensor. Fuel cells use either hydrogen or alcohol to generate electricity. Since people don't breath out hydrogen, then this test uses ethyl alcohol as the fuel to generate electricity. That electricity is displayed on the screen as the blood alcohol content.

The legal limit is 0.08% w/v which is 0.08 grams per 100mL. A person has about 5 liters of blood, so how many grams of alcohol is in their blood?
0.08g x 5000mL = 4 grams.
100mL

(That's only about 5mL of pure alcohol, which is the alcohol in 1/3 of a 12 oz can of beer. However, the alcohol in a can of beer will spread out to all water in the body, not just the water in the blood. So it usually takes 3 to 4 cans of beer to reach 0.08 %w/v)

When ethyl alcohol (ethanol) is completely oxidized (burned) in a fuel cell, 12 electrons are produced as electrical current for each molecule of ethanol. The overall final reaction is this:
C2H5OH + O2 → CO2+ H2O

Balance the above reaction.

Each square centimeter of the ethanol fuel cell membrane "sandwich" produces 0.140 watts of power.  Your cellphone needs about 1 watt of power.

Instead of the fuel cell in the breathalyzer using ethanol in your breath to send electricity to the display, the electricity could be used to charge your cellphone. .

If a person has an alcohol level of 0.10 %w/v that means they have 0.10 grams of alcohol per 100 mL of blood.  The concentration of alcohol in their breath is always 2100 times less than the concentration in the blood.  A person sitting expels about 9 liters per minute.   Ethanol has 8 kilowatt-hours of electrical energy per 1 kilogram of ethanol.   If all of the alcohol they breathe out is converted to electricity using the fuel cell in the breathalyzer, how many watts of power will the breathalyzer put out?  Below is the dimensional analysis of the problem set up in a spreadsheet. You do the math.

 A B C D E F G H I J K L M N 1 0.10% w/v ratio blood to breath Energy content of alcohol Respiration rate cancel minutes cancel m 2 0.10 g alcohol 1 blood 8 kilowatt-hours 9 liter breath 60 min milli = ?? watts 3 100 mL blood 2100 breath 1 kg alcohol 1 minute 1 hour 0.001

Answer:  2 watts  (This is great.  Intoxicated people could power their cellphones using the alcohol they breathe out.)

Cell K1 says "cancel m". What cell has the milli that column K is canceling?

The final answer is in watts, not kilowatts.  What canceled the kilo in kilowatts?

If the respiration rate goes up, will that produce more or less watts of power?
:  (figure out on own).
If the person has a lower blood alcohol level than 0.10%w/v, will that produce more or less watts of power?
:  (figure out on own).

The old breathalyzers used a solution of sulfuric acid and potassium dichromate (K2Cr2O7).  Below is the reaction without the spectator ions (potassium and sulfate ions).

3CH3CH2OH + 2Cr2O72- + 16H+ → 3CH3COOH + 4Cr3+ + 11H2O

The acetic acid produced has 2 oxygen atoms and ethanol only has one oxygen atom. Where did the extra oxygen atom come from?

The left side of the equation shows 16 H+ ions.  Where did those come from?

Water is produced in this reaction.  Here did the 22 hydrogen atoms come from?
Answer: 16 came from the 16 H+ ions.   6 came from the ethanol molecule.

On the exam, you might be asked to balanced one or two of the compounds in the equation, but not the whole equation.

As the alcohol gets converted to acetic acid, the potassium dichromate gets converted to chromium(III) sulfate, Cr2(SO4)3. The alcohol is measured by the color change from the yellow potassium dichromate/sulfuric acid solution to a dark green color of chromium(III) sulfate. So the Breathalyzer had a light pass through the solution and the change in the color correlated to the amount of alcohol in the breath.  Below is the same equation as above but showing all ions.

3CH3CH2OH(aq) + 2K2Cr2O7(aq) + 8H2SO4(aq)→ 3CH3COOH(aq) + 2Cr2(SO4)3(aq) + 11H2O(l)

The initial color of the solution is yellow.  What is responsible for the yellow color?

After the alcohol is turned into acetic acid, the solution is dark green.  What is responsible for that color?

What is the charge on chromium in the dichromate ion (Cr2O72-)?
Answer:  Hint: Oxygen is -2 each. So that's -14 charge.  The two chromium ions must reduce a -14 charge to -2 charge. That requires a +12 charge.  So what are each of the chromium ions?

The below problems are some pulled from the online final at Sapling Learning.  Some of the ones on the actual on-campus final will be variations of the below problems.  A few more from the Sapling Learning final will be on the on-campus final, but those are not shown below.
The IV solution is 5% w/v dextrose (5g/100mL).  How many grams of dextrose would be in 2.00 liters of 5% Dextrose IV solution?

Let's say you were trapped in a mine and you took 1.2 liters of water and did electrolysis on it to get some oxygen, how many grams of oxygen would you get? (Assume each mL of water weighs 1.0 grams)

2H2O → 2H2 + O2

 1.2 liters mass change g to moles ratio from equation mole to g O2 grams O2 1200 g 1 mol H2O 1 mole O2 32 g O2 = ? g O2 18 g. H2O 2 mole H2O 1 mole O2

Water, of course, is H2O.

Which is the most predominant element in water if you base it on its percent of the weight of water?

Which is the most predominant element in water if you base it on its percent of the number of atoms in water?

The doctor injects 7.8 cc (7.8 mL) of this solution. How many milligrams of sodium bicarbonate were injected?

Hint: Remember to set up the calculation so the volume of 7.8 mL and concentration of 84mg/mL gives you just mg.

Teeth begins to dissolve at pH 5. What is the moles per liter of H+ ions at pH 5?
Hint: Two formulas that relate to pH are:
pH= - log (H+ concentration)       H+ concentration = 10-pH

Orange juice has a pH of about 4. Sipping on it would dissolve your teeth. You want to dilute one liter of orange juice with water so that it would have a pH of 6. That way you could sip on it without dissolving your teeth. To what volume would you need to dilute 1 liter of orange juice to make it a pH of 6?
Hint: pH 4 is 10-4 moles per liter. You want to get it to pH 6. How many times larger is pH 4 compared to pH 6? That is how many times larger volume you need.

Hard water usually has calcium dissolved in it. The source is often calcium carbonate (CaCO3) or calcium chloride (CaCl2). To the left is a molecule of soap.  In water the long chain of soap has a negative one charge (-) and the sodium that was attached has a plus 1 (+) charge. Because of its charge, calcium in hard water grabs onto two soap molecules and causes them to come out of solution to form soap scum.  Four ions were mentioned above.  What are the charges on the calcium, carbonate, chloride, and sodium ions (in that order)?
The on-campus exam for CHM130 will be very similar to the practice exam above.