Interesting questions sent in by an avid reader of SimpleChemConcepts.com.

Question:

“I want to ask if i place 1000 Chlorine atoms into water, will i obtain 1000 Hydrogen ions ? I would really appreciate if you could reply asap ! “

PS: What do you think? Write me your suggested answers at the Comment Section below.

Following is a question that was sent to me recently by a local students.
This is a question based on the Properties of Acids and is getting popular in many of the Preliminary Exams in local Top Secondary Schools.

Q )Sulphuric acid is a dibasic acid because:
A. each molecule contain 2 hydroxide ions
B. each molecule can produce 2 hydrogen ions
C. one mole of the acid contains two atoms of hydrogen that can be replaced by a metal
D. sulphuric acid can only be neutralized by 2 bases
E. sulphuric acid has the usual properties of an acid, but is also a dehydrating agent

Try working out the question before checking the answer and reasoning below. (more…)

(Image by Eff Bee)

In the Chapter on Acids & Bases, we learned that Magnesium Hydroxide Mg(OH)2, an Basic Oxide is used to make toothpaste. 

After each meals, there will certainly be a significant amount of food substances that are stuck in-between our teeth. Overnight, bacteria in these food substances will secrete acids that will corrode our teeth and causes tooth decay. Magnesium Hydroxide(an Basic Oxide) has the basic properties and will neutralize the acids between the teeth to form neutral salt and water, which is gentle to our teeth. Simple concepts isn’t it.

This post i will talk about something more interesting in ‘Striped Toothpaste’.

Q) How do they get the stripes in the toothpaste?

Answer is easy. The manufacturer load toothpaste tubes from the flat end with parallel layers of paste and when you squeeze, the layers pass through the nozzle as stripes. According to Discovery Channel Documentaries, manufacturers used to put red paste (which is the stripe) in first. Then they would add the white paste on top. As you squeezed, the white paste would push through an inner tube, and be joined by the red coming through holes in the tube near the nozzle.

How about a little bit more on the brief history about Toothpaste:

• 1st known tooth powder was used in Egypt around 5000BC and included egg-shells and ox hooves
• Early toothpastes had ingredients such as dried animal parts, honey and powedered charcoal
• Europeans didn’t use toothpaste until 1800s and it contained chalk and pulverised brick
• Dr. Washington Sheffield invented the Toothpaste Tube in 1892
• Striped tootpaste was invented in England nearly 50 years ago

Amazing isn’t it??

This is an application question on Acids, Bases & Salts that was sent to sean@simplechemconcepts.com by a local “Student X” to be shared and discussed with “chemists” in the world. Student X has also contributed her ideas and answers with the question.  Do leave some comments for Student X and other students reading this Chemistry Blogsite. Btw, i need to empahsize that it is ok to make mistakes now as we discussed questions. It is definitely better to make mistakes now as compared to mistakes during your examinations.

Question:
Use your knowledge of the nature of acids, bases and salts to explain the following observations or practices.

Among other ingredients, cake mixes contain a solid mixture of tartaric acid and sodium hydrogen carbonate. The mixture can only “rise” if water is added.

Student X’s suggested answer:
“Tartaric acid reacts with sodium hydrogen carbonate to give metal salt + water + carbon dioxide. Carbon dioxide released is trapped in the mixture, thus causing the mixture to “rise”.”

PS: Check out “Comments” below for suggested answers.