List of Topics

SfC Home > Physical Science > Chemistry >


Feedback Q&A on Chemistry

by Ron Kurtus

Readers have sent in a total of 553 comments and questions on Chemistry issues. They are listed according to date.

You can read them to further your understanding of the subject.

List of next 10 letters




Uses of Nitrogen Questions for science project USA
Order of Elements in a Formula Correction in formula USA
Polar Molecules Why do nonpolar solutes tend to adhere China
General Name the following compounds Nigeria
Uses for Hydrogen Which is the lightest gas? Ghana
Polar Molecules Is an apple a polar molecule? Pakistan
Chemistry Basics Wants objective questions Pakistan
Order of Elements in a Formula Order of elements in a formula Pakistan
Hydrogen About hydrogen India
Hydrocarbon Bonding Azeotropic Australia

Next 10

First 10 letters

Questions for science project

Topic: Uses of Nitrogen


April 9, 2016

Hi, my name is Jennifer. I am emailing you because this is for my science class project and my subject was on nitrogen. And just wondering if you could answer at least two questions for me. Q1: Is nitrogen good or bad for you? Q2: when was nitrogen discovered for these uses? Please answer ASAP, please and thank you. Thank you for your time to email this!

Jennifer - USA



Since nitrogen makes up about 78% of the air you breathe, it certainly is not bad for you. What makes it good for you is that it makes sure you don't get too much oxygen at once.

Nitrogen is a key component of biological molecules such as proteins (which are made from amino acids, and nucleic acids. The nitrogen cycle in nature is very important.

Nitrogen was discovered by Daniel Rutherford in 1772 at Scotland.

I hope that helps. Best wishes for success in your science project.

Back to top

Correction in formula

Topic: Order of Elements in a Formula


January 28, 2016

On your page regarding the order of elements in a chemical formula, you made the following statement:

"Most oxides will end in multiples of O, no matter what the alphabetical order. A good example is silicon dioxide: SO2"

However, I would just like to point out this (referring to the EXAMPLE) is wrong - I don't know if you are trying to refer to sulfur dioxide or SiO2. Just wanted to let you know so you could fix it! By the way, your page is amazing, super-informative and really helps me - thank you so much!

Shada - USA



Thanks for letting me know about that typo. I corrected the formula to be SiO2 in the Order of Elements in a Chemical Formula page.

I'm also glad the material has been useful to you.

Best wishes in your studies.

Back to top

Why do nonpolar solutes tend to adhere

Topic: Polar Molecules


January 9, 2016

I have a question
Explain why two nonpolar solutes (or nonpolar groups) tend to adhere to each other in aqueous solutions

qun - China



This is known as the hydrophobic effect, where nonpolar substances to aggregate in aqueous solution and exclude water molecules. This occurs because interactions between the hydrophobic molecules enable the displaced water molecules to make hydrogen bonds more freely with each other and increase the number of hydrogen bonds they are involved with, thereby decreasing the overall free energy.

I hope that answers your question.

Back to top

Name the following compounds

Topic: General


December 6, 2015

what is the Iupac name of the following compounds

Musa - Nigeria



I am sorry, but I do not have that information.

Back to top

Which is the lightest gas?

Topic: Uses for Hydrogen


December 2, 2015





The Hydrogen molecule (H2) weighs 2 atomic units (AU), while the Helium atom is heavier and weighs 4 AU.

The problem is that Hydrogen is highly inflammable, thus Helium is usually used in balloons, because it does not burn and is safer.

Back to top

Is an apple a polar molecule?

Topic: Polar Molecules


October 23, 2015

Apple is polar molecule or non-polar molecule......?

M.Naveed - Pakistan



An apple is made up of many different types of molecules. Some may be polar and some non-polar.

If you select a specific molecule or material in an apple, you can find whether it is polar or not.

Back to top

Wants objective questions

Topic: Chemistry Basics


October 21, 2015

please kindly send me an objective type questions

haseeb - Pakistan



I'm sorry but the only questions we have right now are in the Mini-Quiz. However, there is a Graded Chemistry test you can take.

Back to top

Order of elements in a formula

Topic: Order of Elements in a Formula


September 7, 2015

hi sir, I have a question that why we write Carbon first and then Hydrogen in formula of Benzene..?? and is there any general rule for order of elements in formulas other than Hill system!; thank you very much...!

husnain - Pakistan



The Hill system states that carbon is listed first and then hydrogen in hydrocarbons. Thus the formula for Benzene is C6H6.

In ionic compounds such as NaCl, the positive ion is listed first.

Another rule is that oxides end in O and acids start with H in most cases.

Back to top

About hydrogen

Topic: Hydrogen


August 16, 2015

How can I use hydrogen?

alpesh - India



You can use as well as create hydrogen in chemical reactions. It was once used in balloons but proved to be dangerous, because it it inflammable.

Back to top


Topic: Hydrocarbon Bonding


July 16, 2015

Can 80% Propane be bonded with 20% Ethane to be fused together to be near azeotropic

Charles - Australia



I'm sorry, but I don't have that information.

Back to top

Next 10


Hopefully, this reader feedback has helped provide information about Chemistry issues.

Be chemically active

Resources and references

Ron Kurtus' Credentials


Chemistry Resources


(Notice: The School for Champions may earn commissions from book purchases)

Top-rated books on Chemistry

Questions and comments

Do you have any questions, comments, or opinions on this subject? If so, send an email with your feedback. I will try to get back to you as soon as possible.

Feel free to establish a link from your website to pages in this site.

Where are you now?

School for Champions

Chemistry topics

Feedback Q&A on Chemistry

Chemistry topics





Mixing things together


Graded tests

Also see

Let's make the world a better place

Be the best that you can be.

Use your knowledge and skills to help others succeed.

Don't be wasteful; protect our environment.

You CAN influence the world.

Live Your Life as a Champion:

Take care of your health

Seek knowledge and gain skills

Do excellent work

Be valuable to others

Have utmost character

Be a Champion!

The School for Champions helps you become the type of person who can be called a Champion.