ChemGoals

Thermodynamics in one chart:

A very nice presentation of Thermodynamics concepts in this link:

https://chemed.chem.purdue.edu/genchem/topicreview/bp/ch21/chemical.php

Do read and get benefitted!

Energy, Enthalpy, and the First Law of Thermodynamics Thermodynamics is defined as the branch of science that deals with the relationship between heat and other forms of energy, such as work. It is frequently summarized as three laws that describe restrictions on how different forms of energy can be interconverted. Chemical thermodynamics is the portio...

Excellent video explaining Ionic Equilibria concepts.

Ionic Equilibrium (Full Revision and Concepts) | JEE Main, NEET, AIIMS The first video of the full revision series where we deal with all the concepts and important questions in the chapter 'Ionic Equilibrium'. Link for the note...

Thermodynamics:

You can practice MCQ's here and ask if you have doubt in any question:

1. How many valence electrons does an oxygen atom have?
(a) 2
(b) 6
(c) 8
(d) 16

2. Fluorine atoms tend to...?...when they form chemical compounds with metals.
(a) lose electrons
(b) gain electrons
(c) neither lose nor gain electrons...they usually share electrons equally with metals.
(d) Fluorine atoms do not form compounds with other atoms...fluorine is an inert gas.

3. The identity of an element is determined by...
(a) the number of its protons.
(b) the number of its neutrons.
(c) the number of its electrons.
(d) its atomic mass.

4. The probability area that best represents the shape of an atomic 3p orbital is...

5. Which of the following is the correct electron-dot formula for water?

6. Which of the following is the correct electron-dot formula for carbon dioxide?

7. Which of the following represents the correct formula for aluminum oxide?
(a) AlO
(b) Al2O3
(c) AlO2
(d) Al2O

8. Which of the bonds, shown by the dash, has the greatest polarity?
(a) H-Cl
(b) H-NH2
(c) H-OH
(d) H-SH

9. What is the major attraction between water molecules in the solid physical state?
(a) dipole-dipole interactions
(b) electrostatic interactions between charged atoms
(c) hydrogen-bonds
(d) physical entanglement of the molecules

10. Which of the following is the correct name for NaHCO3?
(a) sodium hydrogen carbonate
(b) sodium acetate
(c) nitrogen hydrogen carbonate
(d) sodium hydrogen carbon trioxide

11. Which of the following electron configurations represents the electron configuration for a magnesium cation...Mg2+?
(a) 1s22s22p63s2
(b) 1s22s22p63s23p2
(c) 1s22s22p6
(d) 1s22s22p4

12. What would be the volume in liters of 640 g of oil if the density of the oil is 0.8 g/mL?
(a) 800 liters
(b) 0.8 liter
(c) 512 liters
(d) 0.5 liters

13. What is the formal charge of the oxygen atom of the following compound?
(a) +3
(b) +1
(c) -2
(d) -3

14. How many milligrams are in 0.2 decigrams?
(a) 20 milligrams
(b) 2000 milligrams
(c) 0.002 milligram
(d) 0.00002 milligram

15. What happens when a fluorine atom becomes a fluoride ion in a chemical reaction?
(a) A proton is gained by the nucleus.
(b) A proton is lost by the nucleus.
(c) An electron is lost from one of the outer orbitals.
(d) An electron is added to one of the outer orbitals.

16. Which of the following orbital box diagrams represents silicon, which has 14 electrons?

Figure enclosed here!

When you’re studying organic chemistry, keep these helpful reminders close by because they highlight some of the most important concepts you’ll need to understand organic chemistry:

1. Electronegativity increases as you go up and to the right in the periodic table.

2. In reaction mechanisms, arrows show the movement of electrons; the tip of the arrow points to where the electrons are going.

3. Resonance is a stabilizing feature of molecules; molecular stability generally increases as the number of resonance structures increases.

4. Bronsted-Lowry acids are proton donors; Bronsted-Lowry bases are proton acceptors.

5. Strong acids have weak (stable) conjugate bases.

6. Conformation refers to the way a molecule folds itself in three-dimensional space based on the rotation around carbon-carbon single bonds; configuration (such as R or S configuration of a chiral center or cis or trans configuration of double bonds) refers to the specific orientation of atoms, which can change only through a chemical reaction.

7. Only chiral molecules have enantiomers; enantiomers rotate plane-polarized light in equal and opposite directions.

8. Molecules with chiral centers that have a plane of symmetry are called meso compounds; meso compounds are achiral.

9. In order to have diastereomers, molecules generally have to have two or more chiral centers.

10. Most organic reactions are driven by an electron-rich species (a nucleophile) attacking an electron-poor species (an electrophile).

11. Double bonds are stabilized by alkyl substituents.

12. Tertiary carbocations are more stable than secondary carbocations; secondary carbocations are more stable than primary carbocations. Allylic carbocations and benzylic carbocations are about as stable as secondary carbocations.

13. Triple bonds are shorter than double bonds; double bonds are shorter than single bonds. In terms of bond strength, reverse is true!

14. Electrophiles are Lewis acids (electron acceptors); nucleophiles are Lewis bases (electron donors).

15. Weak bases are good leaving groups; strong bases are bad leaving groups.

16. Nucleophilicity generally parallels basicity. Typically, strong bases are also good nucleophiles.

17. Primary halides undergo SN2 substitution; tertiary halides undergo SN1 substitution.

18. Aromatics have 4n + 2 pi electrons; anti-aromatic compounds have 4n pi electrons. All electrons in both of these are in resonance/conjugation. Non aromatic does not have resonance.
Stability order:

aromatic>non>>anti

19. Substituents on aromatic rings with lone pairs on the ring-attaching atom are ortho-para directors.

Keep Cheming!! :D

You can review Bohr's model for Hydrogen Atom from this video.

Bohr’s Model for Hydrogen Atom Class 11: Chemistry: Structure of Atom-I: Bohr’s Model for Hydrogen Atom

Can anyone tell the reason?