Which molecular formula is also an empirical formula?

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, H2O2, we can see again that we can divide by 2 and therefore this formula is not empirical either. Choice 3, N2H4 can be divided by 2, and choice 4 N2O5 can not be divided any further since 2 and 5 do not have a common divisor. Therefore, choice 4 is the correct answer.

Compared to a potassium atom, a potassium ion has

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 lost 1 electron. Therefore, a potassium ion has a smaller radius since it has less electrons. P.S. The number of protons gives the identity of the element. Therefore, an atom or an ion of potassium must always have the same number of protons (19). To schedule an a tutoring ses

How to determine the overall reaction order?

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 reactants listed in the rate law. Thus, Rate = k[A]^1[B]^2, is third order (1+2=3), and Rate = k[A] is first order since there is only one reactant with the exponent equal to 1. Check out our incredible chemistry tutor in NYC and schedule a session. #chemistry

Which amino acid has the lowest isoelectric focus point?

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 acidic, basic or neutral. Lysine is a basic amino acid and therefore should have a high pI. Arginine is also basic and should also have a high pI. Glutamine is a polar neutral amino acid, and thus can be eliminated. Aspartate is an acidic amino acid and must have a low pI.

What is the effect of unsaturated acyl chains on the fluidity of the membrane?

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. To schedule a session with a great biochemistry tutor in NYC or online, click here.

What is the function of gall bladder

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 do! These charged ions separate fat molecules from one another, thus increasing surface area and allowing for digestive enzymes to go to work. This helps with the digestion and absorption of fats. To learn more biology, and get in touch with our incredible biology tutors in N

Why do we have "goose bumps"?

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 tiny muscles at the base of each hair, known as arrector pili muscles, contract and pull the hair erect. As the hair "stand up" a layer of insulation is created trapping in the heat and not letting it escape, warming us up. Sometime in the distant past, this mechanism was extre

Strength and length of different bonds

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 order of length is opposite of that of strength, the triple bond is the shortest, double bond is in the middle, while the single bond is longest. To learn more organic chemistry, click here and read about our amazing organic chemistry tutor in NYC and online #organicchemistry

When people receive organ transplants, they often need to take medications that decrease immune resp

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 decrease the immune response/ weaken immune system. This is due to the fact that our body attacks any foreign particles that come inside since it sees them as harmful pathogens. The antibodies in our body recognize and attach to antigens in order to get rid of them. Therefore, th