chapter 2 week 1/18/21

The bonding of calcium, phosphorus, and other elements produces mineral crystals that are found in bone. This is an example of a(n) ________ reaction. catabolic synthesis decomposition exchange

synthesis

Nitrogen has an atomic number of seven. How many electron shells does it likely have? one two three

two

Which of the following is a molecule, but not a compound? H2O 2H H2 H+

H2

The characteristic that gives an element its distinctive properties is its number of ________. protons neutrons electrons atoms

protons

Chewing a bite of bread mixes it with saliva and facilitates its chemical breakdown. This is most likely due to the fact that ________. the inside of the mouth maintains a very high temperature chewing stores potential energy chewing facilitates synthesis reactions saliva contains enzymes

saliva contains enzymes

A substance formed of crystals of equal numbers of cations and anions held together by ionic bonds is called a(n) ________. noble gas salt electrolyte dipole

salt

The energy stored in a foot of snow on a steep roof is ________. potential energy kinetic energy radiant energy activation energy

potential energy

When an atom donates an electron to another atom, it becomes an ion an anion nonpolar all of the above

an ion

________ reactions release energy. Catabolic Exergonic Decomposition Catabolic, exergonic, and decomposition

catabolic, exergonic, and decomposition

Which of the following statements about chemical bonds is true? Covalent bonds are stronger than ionic bonds. Hydrogen bonds occur between two atoms of hydrogen. Bonding readily occurs between nonpolar and polar molecules. A molecule of water is unlikely to bond with an ion.

covalent bonds are stronger than ionic bonds

AB→A+B is a general notation for a(n) ________ reaction. anabolic endergonic decomposition exchange

decomposition

Which of the following combinations of atoms is most likely to result in a chemical reaction? hydrogen and hydrogen hydrogen and helium helium and helium neon and helium

hydrogen and hydrogen

The smallest unit of an element that still retains the distinctive behavior of that element is an ________. electron atom elemental particle isotope

atom

On the periodic table of the elements, mercury (Hg) has an atomic number of 80 and a mass number of 200.59. It has seven stable isotopes. The most abundant of these probably have ________. about 80 neutrons each fewer than 80 neutrons each more than 80 neutrons each more electrons than neutrons

more than 80 neutrons each

Together, just four elements make up more than 95 percent of the body's mass. These include ________. a.calcium, magnesium, iron, and carbon b. oxygen, calcium, iron, and nitrogen c.sodium, chlorine, carbon, and hydrogen d.oxygen, carbon, hydrogen, and nitrogen

oxygen, carbon, hydrogen, and nitrogen

A molecule of ammonia contains one atom of nitrogen and three atoms of hydrogen. These are linked with ________. ionic bonds nonpolar covalent bonds polar covalent bonds hydrogen bonds

polar covalent bonds