January 22, 2020

Lewis Dot structure is a representation of how electrons are arranged in a molecule.

To correctly draw lewis dot structures we need to follow the following six steps.

1. Calculate the total number of valence electrons

2. Connect atoms in a molecule using bonds

3. Subtract electrons used in bonds from the total electrons calculated in part 1

4. Use remaining electrons to make outer atoms happy (octet, 8 electrons) but rem...

September 11, 2019

SAT Chemistry practice from College Board

The hydrogen ion concentration of a solution prepared by diluting 50. mL of 0.10 M HNO3(aq) with water to 500. mL of solution is

(A) 0.0010 M 

(B) 0.0050 M 

(C) 0.010 M

(D) 0.050 M 

(E) 1.0 M

Answer and Explanation:

One of the key words in this question is diluting. A solution gets diluted when more water is adde...

May 18, 2018

For example 20g of NaCl are dissolved in 100ml of water. Thus, HCl is the solute, water is the solvent, and together they make a solution. For more help with chemistry on all levels, please contact Transformation Tutoring, and our amazing chemistry tutors in NYC, Brooklyn, and online will be happy to help you!

March 28, 2018

Dilution is a common type of problems given to students in the concentration chapter of their chemistry class. To dilute something means to add water to the solution, which will in turn decrease the concentration.

The formula for dilution is M1V1= M2V2

where M1= Molarity 1 

V1 = Volume 1

M2 = Final Molarity

V2= Final Volume

Note, that for this formula your volume can be in any units as long as it is consistent on both sides.


March 22, 2018

SAT II Chemistry practice question.

Topic: Acids and Bases

Which of the following is weakly acidic?

a. 0.1M HCl

b. 0.1M NaCl

c. 0.1M HC2H3O2

d. 0.1M CH3OH

e.  0.1M KOH

Solution: In order for us to answer this question we must know how to identify strong acids and strong bases. We have to memorize strong acids in order to be able to identify them. Strong acids are: HCl - hydrochloric acid, HNO3 - nitric acid, H2SO4 - sulfuric ac...

March 19, 2018

SAT subject test in  Chemistry is administered by College Board. 

Time: The test is 60 minutes long

Number of questions: 85 multiple choice questions

Calculator: Not Allowed

Periodic table that indicated atomic numbers and masses is provided on the test.

Test Dates: Test is offered in August, October, November, December, May, and June.

Practice: College board released 2 official tests that can be purchases on its website...

February 23, 2018

Hydrogen bonding will be exhibited by molecules who have OH, NH, or FH bonds. These forces are especially strong and influence the boiling point  and melting point of the substances that contain them. That is why water H2O has an unusually high boiling and melting point. In organic chemistry substances such as alcohol, amines, and carboxylic acids are the ones that will have hydrogen bonding and will have unusually high...

February 18, 2018

Online chemistry tutor is easy and convenient for both the student and the tutor. 

How does it work? Simple! Transformation Tutoring uses an online tutoring platform that has a white board and video capacity. A student clicks on the link and gets directed to the platform, where he/she can see the tutor and communicate. The white board capacity allows the tutor to draw and write formulas and molecules as well as upload pi...

February 14, 2018

Since regent is a standardized exam, doing a lot of practice is key to your success. Start by doing an exam in the red regents book and going over the explanations in the back for the questions you got wrong or were not sure about. This will also help to identity your weak areas that you can review further with the blue regents book. Do as much practice and as many exams possible. Make sure to und

December 13, 2017

Which substance is an electrolyte?

(1) CCl4

(2) C6H12O6

(3) SiO2  

(4) H2SO4 

Answer and Explanation:

An electrolyte is the substance that is able to conduct electricity. Electricity is the flow of charged particles. Therefore, in order to be an electrolyte, we need to have charged particles. We can remember 3 types of substances that are electrolytes: metals, ionic compounds dissolved in water and strong acids/bases. To be a...

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