Chapter 2, Problem 2RQ

Which small organic molecules make up carbohydrates, lipids, proteins, and nucleic acids?

Beginning physics students are often taught the basic concept of thermodynamic with two phrases: First, you can never win. Second, you can never break even. Explain.

What is the function of DNA?

Which type of bond represents a weak chemical bond? a. hydrogen bond b. ionic bond c. covalent bond d. polar covalent bond

A. The first shell corresponds to the first energy level, and it can hold up to 2 electrons. Hydrogen has one proton, so it has 1 electron and one vacancy. A helium atom has 2 protons, 2 electrons, and no vacancies. B. The second shell corresponds to the second energy level, and it can hold up to 8 electrons. Carbon has 6 electrons, so its first shell is full. Its second shell has 4 electrons and four vacancies. Oxygen has 8 electrons and two vacancies. Neon has 10 electrons and no vacancies. C. The third shell corresponds to the third energy level, and it can hold up to 8 electrons. A sodium atom has 11 electrons, so its first two shells are full; the third shell has one electron. Thus, sodium has seven vacancies. Chlorine has 17 electrons and one vacancy. Argon has 18 electrons and no vacancies. Figure It Out: Which of these models have unpaired electrons in their outer shell?

Which of the following is the carbohydrate, the fatty acid, the amino acid, and the polypeptide? a. +NH3CHRCOO b. C6H12O6 c. (glycine)20 d. CH3(CH2)16COOH

The mutual attraction of opposite charges holds atoms together as molecules in an _______ bond. a. ionic c. polar covalent b. hydrogen d. nonpolar covalent

Visit this website (http://openstaxcollege.org/l/ptable) to view the periodic table. In the periodic table of the elements, elements in a single column have the same number of electrons that can participate in a chemical reaction. These electrons are known as valence electrons. For example, the elements in the first column all have a single valence electron—an electron that can be donated in a chemical reaction with another atom. What is the meaning of a mass number shown in parentheses?

What atom has only one proton? a. hydrogen c. a free radical b. an isotope d. a radioisotope