August 30, 2017

Which molecular formula is also an empirical formula?

(1) C6H6

(2) H2O2

(3) N2H4

(4) N2O5 

Answer and Explanation:

An empirical formula is a formula where the subscripts of the elements are in their lowest whole number ratio. In other words, we can not divide them anymore.

Let's take a look at each answer choice. Choice 1 is C6H6, we can divide both numbers by 6 and therefore this formula is not empirical. Moving to choice 2,...

August 27, 2017

Compared to a potassium atom, a potassium ion has

(1) a smaller radius

(2) a larger radius

(3) fewer protons

(4) more protons 

Answer and Explanation: Let's first look at the periodic table on the reference sheet to find out what kind of ion does potassium have? If we look at the top right of K (potassium), we see the charge plus 1. Therefore, the ion of potassium has a +1 charge. +1 charge means that potassium atom has lo...

August 24, 2017

In order to determine the overall reaction order, we need to look at the rate law. Rate law has a general formula Rate = k[A]^m [B]^n where A and B are reactants. Rate law can also look like this Rate = k[A]^m if there is only one reactant in the equation or it can have more reactants depending on the equation given.

In order to determine the overall reaction order all we need to do is simply add the exponents of the rea...

August 21, 2017

Which amino acid has the lowest isoelectric focus point?

a. Lys

b. Arg

c. Gln

d. Asp

Isoelectric focus point or pI is the pH at which a protein has no net charge and does not move in an electric field. Isoelectric focus point basically tells us how acidic or basic a protein is. The more acidic the protein is the lower it's pI is. Therefore, looking at the answer choice we must first determine whether these amino acids are ac...

August 18, 2017

Unsaturated acyl chains are hydrocarbons chains that have one or more double bonds. Double bonds create "kinks" in the chains. Thus, fatty acids can not pack compactly with one another and therefore cause more movement in the membrane. A membrane that has lipids with unsaturated acyl chains at high temperature would be most fluid. While a membrane with lipids with saturated acyl chains at low temperature is least fluid.


August 15, 2017

Gall bladder stores bile. Bile is released into duodenum (first part of small intestine) to help with fat digestion and absorption.

 How does bile work? Bile is composed of salts, which are ionic compounds. Fats are nonpolar molecules that clump up together in the polar environment of the duodenum. Therefore, we need something to separate them and allow for the digestive enzymes to get to work. And that's what bile salts...

August 12, 2017

Have you ever noticed "goose bumps" or the hair on your arms "standing up" ? When does it happen and why?

If you pay close attention, you would see that we get goose bumps when it is chilly. Therefore, this has to be a mechanism to regulate our body temperature and warm us up. Does it happen only in humans? Not at all! This mechanism of keeping warm is common to many mammals. 

The principle behind the mechanism is that ti...

August 6, 2017

In organic chemistry, we are often asked to rank the triple, double and single bonds in terms of their strength and length. In a triple bond , 3 pairs of electrons are shared, while in a double bond only 2 pairs are shared and in a single bond, one pair electrons is shared. Therefore it takes more energy to break a triple bond and thus,  triple bond is the strongest, followed by the double bond, and single bond.  The or...

August 3, 2017

1.transplanted organs contain antigens that can trigger white blood cell activity
2. hormones present in replacement organs prevent the synthesis of antibiotics

3. transplanted organs produce their own antibiotics

4. antigens present in these organs attack antibodies already present in the blood 

Answer and Explanation:

Whenever a person receives an organ transplant, he/she received immunosuppressants, or drugs that d...

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