Chemistry (including Biochemistry)/Questions Answered by Expert Chad Welch
| Subject | Date Asked |
| making oils water soiluble | 5/19/2010 |
| Q: I have some essential oils, I would like to put in a spray bottle, with water. Is there some way I ... A: There are many chemists who spend years trying to accomplish the same thing for large corporations. ... | |
| quantifying rate of spoilage | 4/16/2010 |
| Q: I would like to do an experiment for our science fair on the effect fat content has on the rate that ... A: There are a couple of different types of pH strips. One type is also called litmus paper, it turns ... | |
| quantifying rate of spoilage | 4/13/2010 |
| Q: I would like to do an experiment for our science fair on the effect fat content has on the rate that ... A: This sounds like a great experiment. Milk spoils as bacteria decompose components in the milk. ... | |
| urgent chemistry question | 3/22/2010 |
| Q: I have a quesiton, and I hope you can help me with that. my stock solution has the concentration of ... A: This can be solved using the equation M1*V1=M2*V2, where M1 & M2 are the starting and final molar ... | |
| HOCL produed from hydrogen peroxide & chlorinated tap water? | 3/18/2010 |
| Q: Background: I typically use a mix of hydrogen peroxide and tap water (1/4 peroxide cup to 1 gallon ... A: Scott, Anytime chlorine is dissolved in water (as is the case with water treatment) HCl and HOCl ... | |
| Engraving in Iron | 3/16/2010 |
| Q: Sir, I want to engrave some numbers on a vehicle chassis(iron) using acid. What is the best acid I ... A: Kusman, The HCl and Nitric acid mixture is probably your best solution. If the chassis is just iron, ... | |
| chemistry molar ratio help | 3/12/2010 |
| Q: i was given an equation to balance which turned out to be 2Mg+TiCl4=2MgCl2+Ti. then the next ... A: You are on the right track. You got the correct number of moles of Ti. To visualize how you obtained ... | |
| epsom salt crystals | 2/14/2010 |
| Q: I'm helping my daughter with her science project. According to the instructions she was only to add ... A: Sorry that the experiment didn't work out as expected. I'm not sure why your instructions only ... | |
| Gas law | 2/6/2010 |
| Q: How can I calculate the volume of gas produced from a reaction at 20 degree celcius? Is it possible ... A: Bonnie, You are correct you can use the gas laws equation to calculate the volume. If all that ... | |
| mixing bases | 2/4/2010 |
| Q: in an experiment looking for unknowns, is it possible to interchange bases, like substitute one for ... A: Josh, In this case, the two bases would not have made any difference. The halogens all exist as ... | |
| mixing bases | 2/4/2010 |
| Q: in an experiment looking for unknowns, is it possible to interchange bases, like substitute one for ... A: In most cases changing the base will change some aspect of the experiment. Either the reaction ... | |
| alkali metals | 2/2/2010 |
| Q: What is the relationship between atomic radius and melting point? Is the atomic number the same as ... A: Good question, thanks. The atomic radius is the size of the atom. Moving down a column in the ... | |
| order of chemicals? | 1/12/2010 |
| Q: Can H2O be written OH2? Does the order matter? Seems to me that I have one Oxygen and two ... A: Debra, You are correct, OH2 is the same thing as H2O. Tradition dictates that we write the cations, ... | |
| ph and temperature dependence | 1/11/2010 |
| Q: i am a grade 10 student working on a project involving pH and temperature dependence. I carried out ... A: Sigi, The in depth solution to this involves some fairly advanced physical chemistry including the ... | |
| sublimation | 1/5/2010 |
| Q: Is flatulence an example of sublimation? A: Cathy, That is an interesting idea, but no, flatulence is not sublimation. Sublimation occurs when a ... | |
| chemistry | 12/11/2009 |
| Q: i am confused by these two questions and i need your help 1) if i have 136 grams of sulfur, how ... A: Stephanie, You are correct on #1. The units of molar mass are grams/mole. So if you have 136 grams ... | |
| chemistry question | 11/28/2009 |
| Q: So far on this question I tried to convert the wavelength into energy using Planck's constant. I am ... A: Jackie, Thanks for replying back. You are correct to convert the wavelength to energy. The total ... | |
| Salt water test | 11/25/2009 |
| Q: I have a question about a salt water corrosion test. When I was performing this test I used a ... A: Allen, You are correct. The cheaper salt will have more impurities. I did corrosion testing for a ... | |
| CHEMISTRY (HIGH SCHOOL STANDARD) | 11/15/2009 |
| Q: Please can you tell me whether having lots of unsaturated (double) bonds affects a substance's ... A: Julie, I'm not sure what you mean by a substance's thickness. Do you mean the thickness of the ... | |
| chem question | 10/4/2009 |
| Q: Hey I've been stuck on this question for over 2 hours from an old test of one of my professors. ... A: Given the information you have listed here, the correct answer is 7.90g. However, I believe there is ... | |
| Chemistry trivia | 4/20/2009 |
| Q: My son has a science teacher that does something every couple of weeks for extra credit, and also ... A: Patty, Those are geographic coordinates. If you have a program like Google Earth (it is a free ... | |
| calories | 4/20/2009 |
| Q: Can calories be diluted? For example: If you pour a can of soda into a half gallon of water and ... A: Carmela, You are correct. Consuming a can of soda will have the same number of calories as dumping ... | |
| chemistry | 4/18/2009 |
| Q: why a spoon full of full of sugar dissolves more quickly than a sugar cube? A: This is because of the surface area of the sugar cube versus the spoon full of sugar. The only ... | |
| hydrogen flouride | 4/16/2009 |
| Q: why only hf reacts and attacks silicon dioxide and why silicon dioxide is resistant towards all ... A: SEEP, The other halogens are less electronegative so it is not favorable for the SiO2 to undergo a ... | |
| hydrogen flouride | 4/15/2009 |
| Q: why only hf reacts and attacks silicon dioxide and why silicon dioxide is resistant towards all ... A: SEEP, HF undergoes a chemical reaction with the SiO2 to form silicon hexafluoride. Most acids ... | |
| flammable elements | 2/20/2009 |
| Q: (This is for a novel I'm writing) Of Hydrogen, Lithium, Beryllium, Boron, Carbon, Oxygen, Fluorine, ... A: Michael, Of those elements, hydrogen is the most flammable. If you are familiar with the Hindenberg ... | |
| water and evaporation | 11/10/2008 |
| Q: i was wondering how and why water evaporates when it is not exposed to its boiling point. ex. If i ... A: Tyler, That is a good question. To begin to understand it, we need to think about the water on a ... | |
| moles | 9/16/2008 |
| Q: suppose I have a 100g sample of a compound. How would I go about in finding how many moles are in ... A: Naomi, You are almost correct. You do need to find the molar mass. The units of the molar mass are ... | |
| Planet chemical used in medicine? | 9/15/2008 |
| Q: I wanted to know if you knew of any chemical from a plant that is used medicinally. I have to write ... A: Abigail, Thanks for the question. Yes there are numerous medicines in use that are derived from ... | |
| Titration | 8/19/2008 |
| Q: I am studying for the MCAT and I am in fact doing a practice problem but I am not asking you to ... A: Jessica, This is a good question. You have it set up correctly, except that I think a plus sign is ... | |
| Mass of sugar dissolved in water | 8/19/2008 |
| Q: oldie a bit confused..Of you have 2 teaspoons of sugar and they weigh 20 grams, and a glass of water ... A: You are correct; the mass of the sugar water will be 120 g. What does change is the density of the ... | |
| Ions | 4/7/2008 |
| Q: As a general rule is it true that the further away an electron is from the nucleus the less energy ... A: Daniel, Before I answer let me make sure I am understanding your question. When you refer to first, ... | |
| Ions | 4/6/2008 |
| Q: As a general rule is it true that the further away an electron is from the nucleus the less energy ... A: Daniel, As a general rule that is correct. This is known as the ionization potential (see ... | |
| Avrogadro's Number | 4/2/2008 |
| Q: How did Avogadro Find this Number can duplicate his experiment, how? A: Christopher, Avogadro did not determine the number that is attributed to his name. He is best known ... | |
| buffer solution | 2/26/2008 |
| Q: If a buffer solution contains an acid as one component and a base as the other, can those two ... A: Ann, Your assumption is correct. A buffer is made of a weak acid and its conjugate base or a weak ... | |
| chemistry | 2/25/2008 |
| Q: i need to know how to determine the molecular mass of C2H5OH? A: Sade, The molecular mass is just the sum of the individual masses of the elements. On the periodic ... | |
| calcium flouride | 2/9/2008 |
| Q: I am wondering if you can tell me which is the correct formula for calcium fluoride. CaF2 or CaF ... A: Vince, That is partially correct. The larger the molecules become, the less it can be thought of as ... | |
| calcium flouride | 2/9/2008 |
| Q: I am wondering if you can tell me which is the correct formula for calcium fluoride. CaF2 or CaF ... A: Vince, Calcium fluoride is CaF2. In its elemental form fluorine is F2, so the chemical formula ... | |
| gas volumes | 2/8/2008 |
| Q: I need to design an experiment which will allow me to measure the volume of a gas. I am trying to ... A: Loma, STP stands for standard temperature and pressure, which is generally used to refer to 0 ... | |
| phas shifts, opposite of sublimation | 2/7/2008 |
| Q: solid to liquid....melting liquid to solid....freezing liquid to gas.....evaporation gas to ... A: Feiv, Yes, the transformation of a gas to a solid (without the intermediate liquid phase) does ... | |
| gas volumes | 2/7/2008 |
| Q: I need to design an experiment which will allow me to measure the volume of a gas. I am trying to ... A: Loma, The simple answer is that if the first equation were correct, the volume of gas at STP would ... | |
| Salts present in natural water | 1/6/2008 |
| Q: What are the salts that could be found in natural mineral water? Yours Anna A: Anna, Mineral water is a very broad term. There are thousands of commercially available brands of ... | |
| limewater | 11/24/2007 |
| Q: and does it have a set concentration if it's not diluted etc thanks A: Lorna, Yes, lime water is alkaline. It is a saturated solution of calcium hydroxide in water. ... | |
| atoms | 11/22/2007 |
| Q: I have a few questions that have been floating around my head while sitting in my first year chem ... A: Andrea, Good questions. On a molecular level, when an object is broken, the bonds that were ... | |
| molality and molarity | 11/20/2007 |
| Q: Can you explain the difference between molality and molarity? And under which circumstances should ... A: Meg, Molarity is defined as grams of solute per liter of solution. It is determined by weighing the ... | |
| Periodic Table | 10/27/2007 |
| Q: Why are the Lanthanides and Actinides separated from the rest of the table? A: Joo, The only reason is to make it easier to print and display the periodic table. If you go to ... | |
| Need some help understanding concept/process by which to deduce answers... | 10/4/2007 |
| Q: MyHow do I find a)the # of protonc b)the # of electrons, and c)the # of neutrons when given info. ... A: Confused, An element will always have the same number of protons. This is given by the element ... | |
| why warm objects weigh less | 9/25/2007 |
| Q: I was wondering why warm objects weigh less than cool objects. Thanks. A: Jessica, This is a good distinction between mass and weight. The mass of the object doesn't vary, ... | |
| Chem Question | 9/23/2007 |
| Q: Im taking chemistry in college. I dont know how I would go about solving this problem. Thanks. ... A: Qadus, I don't generally answer homework questions on this forum, but I'll give you the steps, if ... | |
| chemistry | 9/22/2007 |
| Q: I'm unclear on the diffrence between the number of electrons in the outer shell and the valence ... A: Debbie, In many cases the valence number does equal the number of electrons in the outer shell. In ... | |
| acetic acid | 9/21/2007 |
| Q: i was just wondering if you can explain one simple thing to me... In the structural formula for ... A: Danny, CH3COOH is shorthand for acetic acid, but the notation doesn't show bonds. A better picture ... | |
| Chemistry | 9/18/2007 |
| Q: How do i tell the difference between what is a heterogeneous mixture and a homogeneous mixture? like ... A: Shelby, A heterogeneous mixture is composed of more than one distinct component. Concrete is made ... | |
| iso | 9/6/2007 |
| Q: In chemistry, what does iso mean? A: Matt, ISO refers to the International Organization for Standardization. I'm not sure why the ... | |
| lab | 9/3/2007 |
| Q: How am I supposed to know if the object is cooled down yet? I think they said I"ll be holding a test ... A: Jeff, You will probably be using a test tube clamp like the ones shown at: ... | |
| atom vs. element | 8/31/2007 |
| Q: Is atom synonymous with element? My textbooks subtly tries to imply they're different, but I don't ... A: Matt, The difference is subtle and has to do with quantity more than anything. As I'm sure you ... | |
| engines | 8/25/2007 |
| Q: how does water damage parts of engines? thankyou A: Victor, There are primarily two reasons that water is bad for engines. First, most engines are made ... | |
| chemistry | 8/24/2007 |
| Q: does the pressure in a filled propane tank decrease when the valve is opened? A: Trey, Yes and No. If you have a guage on the tank that shows the pressure inside the tank, then you ... | |
| passive solar heating | 1/22/2007 |
| Q: I'm trying to heat many acres of plastic tunnels for Agriculture. The farm agent said to put water ... A: Sandra, Adding calcium chloride (CaCl2) will affect the heat transfer rate of water. The more CaCl2 ... | |
| Mercaptoethanol | 1/17/2007 |
| Q: This may be a trivial question, but what is the chemical structure of mercaptoethanol and what does ... A: Jim, Mercapto (or mercaptan) is another name for a thiol or an -SH functional group. So ... | |
| when magnesium oxidizes | 1/15/2007 |
| Q: i am a sophomore in high school and i recently did a lab in chemistry class where i oxidized ... A: Stephanie, I like the way you think. You started with a metal and ended with a powder. On first ... | |
| Chemistry for Science Fair | 1/15/2007 |
| Q: What is the name of the bacteria that is found in old milk?What makes the color change in when you ... A: Nancy, Milk will contain many different types of bacteria. Some estimates give dozens of varieties ... | |
| Chemistry for Science Fair | 1/14/2007 |
| Q: What makes the color change in when you add Bromthymol blue to fresh milk, five day old milk, 10 day ... A: Nancy, Bromothymol blue is a common pH, or acid, indicator. Most pH indicators work by changing ... | |
| Weight of Water | 8/22/2006 |
| Q: How much does water weigh? For example.... how do you figure out how many pounds are in 12 FLUID ... A: Amanda, 1 mililiter of water equals 1 gram. So to figure out how much 12 Fl. Oz. weighs, we have to ... | |
Chemistry (including Biochemistry)
Answers by Expert:
Chad Welch
Top Expert on this page
Expertise
I specialize in general chemistry, analytical and instrumental chemistry and inorganic chemistry.
Experience
3 years of work experience as an analytical chemist at Blanchard Metals and IM Flash Technologies. At Blanchard Metals I analyzed and adjusted the chemistry of plating baths. At IM Flash Technologies I work in a clean room checking the process chemicals and equipment used to manufacture semiconductors.
Organizations
American Chemical Society (ACS)
Education/Credentials
BS in Chemistry (ACS Certified)
Awards and Honors
American Institute of Chemists, Chemist of the Year 2005-2006
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