Question | Answer |
most abundant element on earth | oxygen |
oxygen is _____ percent the volume of atmospheric air | 21% |
oxygen is _____ percent the mass of water | 89% |
means "acid former" | oxygen |
how many valence electrons does oxygen have? | 6 |
what is oxygen's oxidation number? | -2 |
3 words to describe oxygen: | colorless, odorless, tasteless |
T/F: Oxygen is lighter than air. | False. Oxygen is heavier than air. |
Is oxygen soluble in water? | slightly |
What can liquefy and solidify oxygen? (2 things) | Extreme pressure and Low temperature |
oxygen will react with other substances very rapidly at what temperatures? | high temperatures |
oxygen reacts with metallic and nonmetallic elements to form _____ | oxides |
what process does oxygen support, helping other things burn? | combustion |
considered a ______ agent | oxidizing |
Define Oxidation (4 ways) | 1) addition of oxygen to a substance, 2) the removal of hydrogen from a substance, 3) the removal of electrons from a substance, 4) the increase in oxidation number of a substance |
reduction is the _____ of oxidation | opposite |
Define Reduction (4 ways) | 1) removal of oxygen from a substance, 2) addition of hydrogen to a substance, 3) addition of electrons to a substance, 4) the decrease in oxidation number of a substance |
the substance reduced in an oxidation-reduction reaction is called the _____ agent | oxidizing |
the simplest form of an oxidizing agent is | oxygen |
the substance oxidized in an oxidation-reduction reaction is called the _______ agent | reducing |
the simplest form of a reducing agent is | hydrogen |
when an element exists in two or more different forms, each with its own physical and chemical properties | allotropic |
Three Allotropic forms of oxygen | O (nascent oxygen), O2 (molecular oxygen), O3 (ozone) |
the most abundant element in the universe | hydrogen |
T/F: there is a lot of free hydrogen in the atmosphere | false, there is very little free hydrogen in the atmosphere |
atomic mass of one atom of hydrogen | 1 amu |
oxidation # for hydrogen | +1 |
T/F: hydrogen is lighter than air | true |
is hydrogen soluble in water? | slightly |
hydrogen burns with a _____, _____ flame, forming _____ | hot, blue, water |
does hydrogen support combustion? | no |
hydrogen acts as a ______ agent | reducing |
means "water producer" | hydrogen |
the most abundant compound | water |
water covers _____ percent of the earth's surface | 75% |
water is considered a _____ molecule, where ____ atoms of hydrogen are bonded to ____ atom of oxygen, forming a bond angle of _____ degrees | bent, 2 hydrogen, one oxygen, angle of 105 degrees |
how are H and O bonded? | covalent |
molecular mass of water | 18 amu |
water freezes at | 0 degrees C |
water boils at | 100 degrees C |
heat of vaporization for water | 540 calories/gram |
heat of fusion for water | 80 calories/gram |
specific heat of water | 1 calorie/gram per degree C |
is water a good solvent for many substances? | yes |
an intermolecular attractive force between a hydrogen atom on one water molecule to an oxygen atom on another molecule | hydrogen bonding |
the force that causes the surface of a liquid to contract | surface tension |
surface tension is important to embalming because it occurs at interfaces of _____ and _______, which interferes with _____ of embalming chemicals from the capillaries to the tissues | solutions and cell membranes, interferes with the diffusion of embalming chemicals |
to alleviate the problem of surface tension in embalming, what is introduced to most embalming fluids: (3 names) | surfactants, wetting agents, surface active agents |
is water stable? | yes |
water reacts with the alkali metals to liberate _____ | hydrogen |
water reacts with metallic oxides to form ____ | bases |
water reacts with nonmetallic oxides to form _____ | acids |
water that contains certain minerals in solution that destroy the cleansing action of soap | hard water |
three minerals which contribute to water hardness | calcium, magnesium, and iron (II) |
water hardness that can be removed by boiling and filtration | temporary hardness |
water hardness due to the presence of bicarbonate salts of Ca and Mg | temporary hardness |
water hardness caused by the chloride and sulfate salts of Ca and Mg | permanent hardness |
water hardness that can be removed by chemical treatment and filtration | permanent hardness |
presence of _____ calcium in the blood is very important in the blood-clotting process | ionized |
hard water should be avoided to dilute embalming fluid because it will cause | blood clotting |
to reduce effect of hard water on embalming, what are added (2 names) | water-conditioning agents, anticoagulants |