Chemistry joke somewhat related to day-light savings:
Question: Why do chemists like nitrates so much?
Answer: They're cheaper than day rates.
Search found 17 matches
- Wed Mar 09, 2016 4:51 pm
- Forum: Polyprotic Acids & Bases
- Topic: PUBLIC SERVICE ANNOUNCEMENT
- Replies: 1
- Views: 610
- Mon Feb 22, 2016 3:39 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3686239
- Sun Feb 14, 2016 11:06 am
- Forum: General Rate Laws
- Topic: 15.17
- Replies: 1
- Views: 418
Re: 15.17
When you want to figure out the reaction order of one reactant (let's say A for example), choose an experiment in which the initial concentrations of the other reactants (B and C) stay the same. For the two experiments that you choose to compare, only the initial concentrations of A should be differ...
- Mon Feb 01, 2016 1:33 pm
- Forum: Balancing Redox Reactions
- Topic: A Little Helpful Tip
- Replies: 1
- Views: 496
A Little Helpful Tip
In the course reader, the acronym "LEO" is used as a way to remember that "Losing Electrons is Oxidation". Another great way to remember this by using the acronym "OIL RIG" (a device used to extract natural gas), which stands for "Oxidation Is Loss" and "...
- Mon Jan 18, 2016 1:40 pm
- Forum: Phase Changes & Related Calculations
- Topic: Week 2 Chemistry Jokes!
- Replies: 4
- Views: 2080
- Tue Jan 12, 2016 4:15 pm
- Forum: Phase Changes & Related Calculations
- Topic: negative and positive work
- Replies: 1
- Views: 369
Re: negative and positive work
I think when we use this version of the work equation (W = F x D), we can do work on an object in any state of matter as long as we apply a force (F) and manage to move the object over a certain distance (D). However, I think the modified version of the equation (W = P x deltaV), can only be used on...
- Sun Jan 10, 2016 3:46 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Delta H of Formation of Diatomic Molecules
- Replies: 2
- Views: 726
Re: Delta H of Formation of Diatomic Molecules
I think that the formation of gaseous Br2 would have a delta-H value that is something other than zero; it's likely that you'll only ever find the delta-H of Br2 to be zero when in it's in its natural liquid state.
- Sun Nov 29, 2015 9:50 pm
- Forum: Bronsted Acids & Bases
- Topic: Bronsted Acid and Base
- Replies: 1
- Views: 511
Re: Bronsted Acid and Base
Common compounds that can act as both an acid and base are buffers - they can either provide or accept protons in order keep a solution at a certain pH. Although buffers can act in either capacity, a buffer will often be classified as a weak acid or weak base. So although the chemical makeup of a bu...
- Sun Nov 22, 2015 8:24 pm
- Forum: Polyprotic Acids & Bases
- Topic: Ka for Polyproptic Acids
- Replies: 2
- Views: 725
Re: Ka for Polyproptic Acids
After each reaction that occurs as a polyprotic acid dissociates, the Ka gets smaller and smaller. This is because it is harder for the acid to lose protons as it acquires a negative charge.
- Sun Nov 15, 2015 12:23 pm
- Forum: Biological Examples
- Topic: Summary of Biological Importance
- Replies: 2
- Views: 711
Re: Summary of Biological Importance
Coordination compounds involving chromium helps control blood sugar by helping insulin function. Coordination compounds involving iron form myoglobin and hemoglobin complexes that transport oxygen through the bloodstream. Coordination complexes involving cobalt are involved in the role of B-vitamins.
- Sat Nov 07, 2015 4:59 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Approximations
- Replies: 1
- Views: 352
Re: Approximations
The reason why equilibrium expressions are only considered approximations may be because we only include gaseous and aqueous compounds in the expressions. Solids and liquids are excluded because they undergo extremely insignificant changes in concentration. However, those changes are still changes a...
- Sat Oct 24, 2015 3:58 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: helpful VSEPR chart
- Replies: 1
- Views: 424
Re: helpful VSEPR chart
Thank you!
- Sat Oct 24, 2015 3:16 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Determining bond angles
- Replies: 3
- Views: 1002
Re: Determining bond angles
Oops, in the first example I meant C2H4, not C2H2.
- Sat Oct 24, 2015 2:50 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Determining bond angles
- Replies: 3
- Views: 1002
Re: Determining bond angles
Looking at C2H2 as a simple example, we know that each carbon has a trigonal planar VSEPR shape. Therefore the bond angle of every atom surrounding each of the two carbons will be 120 degrees. Keep in mind that three atoms are required to form an angle, like three points in geometry. For more comple...
- Thu Oct 15, 2015 4:51 pm
- Forum: Empirical & Molecular Formulas
- Topic: Empirical Formula
- Replies: 1
- Views: 642
Re: Empirical Formula
Let’s imagine that we determined that 100 grams of a certain compound had 40.9 grams of carbon, 4.58 grams of hydrogen, and 54.5 grams of oxygen. Finding the empirical formula of this compound means finding the basic ratio of each of the elements. To do this, we need to know how many moles of each e...
- Thu Oct 08, 2015 11:08 pm
- Forum: Properties of Electrons
- Topic: Homework Problems 1.33 and 1.37
- Replies: 1
- Views: 608
Re: Homework Problems 1.33 and 1.37
For #1.33, we need to use the "de Broglie" equation, which is "lamda=h/(m*v)". Lambda is wavelength, "h" is Planck's Constant (6.626*10^-34 J*s), "m" is the mass of an electron (9.10939*10^-31 kg), and v is the velocity of the electron. (a) We are given the ve...
- Fri Oct 02, 2015 12:37 am
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Deriving ΔV from the Uncertainty Equation
- Replies: 1
- Views: 470
Deriving ΔV from the Uncertainty Equation
Knowing that Δp*Δx = h bar/2, may I please know how one can manipulate this equation to find the equation for ΔV (in detail)? Measured in meters per second, why is ΔV used to denote uncertainty in position in the answer and not ΔX? These questions arise from the context of problem number 43 of chapt...