CHEMISTRY COMMUNITY

Evamae Bayudan 1B

I understand that increasing the temperature of an endothermic reaction shifts the reaction to towards the products, but how do we know if the reaction is endothermic or exothermic without it being directly stated in the problem or without being told the ΔH°.

Evamae Bayudan 1B

Yeah, I know the answers would be the same; I just thought Lavelle could put it on the "Solution Manuel Errors" list in case others encounter it, too.

Evamae Bayudan 1B

The problem says to consider the equilibrium 3NH3(g) +5O2(g) <--> 4NO(g) + 6H2O (g). I thought the equation has to balanced in order for it to be in equilibrium. The reactant side has 3 Nitrogens and 9 Hydrogens while the product side has 4 Nitrogens and 12 Hydrogens. Shouldn't the 3 coefficient for...

Evamae Bayudan 1B

Here are some more jokes!

Q: Why do chemists like nitrates so much?
A: They're cheaper than day rates.

Q: What is the show cesium and iodine love watching together?
A: CSI

Evamae Bayudan 1B

Nitrogen is more electronegative than sulfur because it's electronegativity is 3.0 while sulfur's electronegativity is 2.6. There is a chart on the top of page 78 in the textbook if you want to look at the trends of the other elements.

Hope this helps!

Evamae Bayudan 1B

Antibonding pairs result in the raising of energy, which causes destabilization. The more antibonding pairs there are, the more likely it is unstable. Antibonding pairs also decrease the bond order of compounds, which in turn decreases the bond strength and increases the bond length.

Evamae Bayudan 1B

Radicals play an important role in our lives. Foods become rancid and plastics degenerate in sunlight all because of radicals. Aging is also caused by radicals. Antioxidants can react with radicals to delay their damage. There is a section called "Radicals and Biradicals" in the textbook o...

Evamae Bayudan 1B

There is a table and a chart on page 82 of the textbook stating the average bond lengths between atoms. Do we have memorize this chart for the quiz, midterm, or final? Also, do we have to memorize the dissociation energies for each bond on page 80?

Thank you

Evamae Bayudan 1B

The ground state electron configuration for Sn is [Kr]4d^10 5s^2 5p^2. Sn ^ 4+ has a +4 charge, so you would take away 4 electrons. You would remove the electrons 5s^2 and 5p^2 to gain the +4 charge, leaving you with [Kr]4d^10. In the textbook, it says "The d-electrons of the p-block atoms are ...

Evamae Bayudan 1B

The mass of an electron is different from the mass of a neutron. The mass of an electron is 9.10938 × 10^-31kg while the mass of a neutron is 1.674927351×10^-27kg. Since problem 1.27 asks for the velocity of a neutron, you would use 1.674927351×10^-27kg as the mass.

Evamae Bayudan 1B

When you're doing k=1/2mv^2, the mass is the mass of the electron. The mass of an electron is a constant number, and it can be found on the back of our periodic table if you bought the course reader. The mass of an electron is 9.10938 x 10^-31kg

Evamae Bayudan 1B

Will we be penalized for putting extra significant figures?

CHEMISTRY COMMUNITY

Search found 12 matches

Endothermic or Exothermic?

Re: Problem 10.77 in textbook

Problem 10.77 in textbook

Re: Chemistry Jokes

Re: Electronegativity of Nitrogen and Sulfur

Re: Antibonding pairs

Re: Radicals and Biradicals

Bond lengths and dissociation energies?

Re: Exceptions to Electron Configurations

Re: 1.27

Re: If ∅ for Na is 150.6 kJ.mol-1, how do I get the mass of

Re: All students read this sig fig post [ENDORSED]