## Search found 14 matches

Wed Apr 25, 2018 11:13 pm
Forum: Einstein Equation
Topic: Difference Between Equations [ENDORSED]
Replies: 4
Views: 330

### Difference Between Equations[ENDORSED]

What is the difference between E=hv and E=hc/lambda? Do you only use E=hv when frequency is given and E=hc/lambda when the wavelength is given?
Mon Apr 23, 2018 10:27 am
Forum: Photoelectric Effect
Topic: Incident Light
Replies: 3
Views: 269

### Incident Light

Is incident light the same as threshold energy?
Mon Apr 23, 2018 9:18 am
Forum: Photoelectric Effect
Topic: What is work function? [ENDORSED]
Replies: 15
Views: 3243

### What is work function?[ENDORSED]

What is the work function? Most of the time it's given in a problem, but I don't understand what is the meaning behind it.
Mon Apr 23, 2018 9:13 am
Forum: Einstein Equation
Topic: Difference Between Equations
Replies: 4
Views: 270

### Difference Between Equations

What is the difference betwee E=hv and E=1/2mv^2? Do these equations give out different types of energy? I don't understand why there's two types of equations and they both equal to "E"
Mon Apr 23, 2018 9:10 am
Forum: DeBroglie Equation
Topic: DeBroglie
Replies: 7
Views: 381

### DeBroglie

How do we know when to use the DeBroglie equation? I'm still a little bit confused where to get "p" in the equation.
Mon Apr 23, 2018 9:03 am
Topic: Black Body? [ENDORSED]
Replies: 13
Views: 1455

### Re: Black Body?[ENDORSED]

Why is it called black body?
Mon Apr 23, 2018 8:59 am
Forum: Quantum Numbers and The H-Atom
Topic: quantum numbers [ENDORSED]
Replies: 3
Views: 277

### Re: quantum numbers[ENDORSED]

I found this link online that talks about quantum number in depth:
https://chem.libretexts.org/Core/Physic ... um_Numbers
Mon Apr 23, 2018 8:57 am
Forum: Photoelectric Effect
Topic: Photoelectric Effect
Replies: 2
Views: 157

### Photoelectric Effect

What is the difference between binding energy and threshold energy?
Wed Apr 11, 2018 4:27 pm
Forum: Empirical & Molecular Formulas
Topic: Empirical Formula
Replies: 2
Views: 219

### Re: Empirical Formula

Since the empirical formula is given, you can find the molar mass of the empirical formula! C=12.01 H=1.008 (since it's H2, you multiply 1.008 times 2) Molar mass of CH2=14gCH2 (2 sig figs from the equation) Always remember that you need to divide actual/theoretical So our actual= 84g.mol^-1 theoret...
Wed Apr 11, 2018 4:19 pm
Forum: Balancing Chemical Reactions
Topic: Balancing equations with fractions [ENDORSED]
Replies: 13
Views: 735

### Re: Balancing equations with fractions[ENDORSED]

Stoichiometric coefficients shouldn't be in fraction form because I think that it would indicate that you have to split an atom in half and that's not possible. It is better if you multiply the whole equation by 2.
Wed Apr 11, 2018 4:15 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 8039
Views: 1411116

### Re: Post All Chemistry Jokes Here

Q: What is the chem formula for "coffee"?
A: CoFe2
Wed Apr 11, 2018 4:05 pm
Forum: SI Units, Unit Conversions
Topic: Moles mols mol? [ENDORSED]
Replies: 21
Views: 2347

### Re: Moles mols mol?[ENDORSED]

Mol/mols is an abbreviation for moles, i don't think it matters. The previous replies are correct, just make sure to not confuse moles with "M" (molarity)!
Wed Apr 11, 2018 3:58 pm
Forum: Properties of Light
Topic: HW #1.7
Replies: 5
Views: 542

### HW #1.7

For homework problem 1.7 letter (A), it gave frequency (v) and the constant is already known (c). We can find the wavelength through this way but it is asking for the final answer in nanometers, what steps do we take to convert the current answer into to nanometers? Question from the textbook: "...
Wed Apr 11, 2018 3:48 pm
Forum: SI Units, Unit Conversions
Topic: Sig Figs
Replies: 9
Views: 581

### Sig Figs

I noticed in the empirical formula problems in in the post module assignment, some of the elements are rounded off. For example Hydrogen (instead of 1.008, it is stated as 1.0), Oxygen (instead of 15.999, it is used as 16), do we stick to this concept where we round the numbers and not put the exact...