Biology - Chemistry of Life 1112Presentation Transcript
Chemistry for Biology Biology ~ Edgar
True or False
Table salt, water, and carbon are all compounds.
The smallest particle of an element is a molecule.
A bathtub full of lukewarm water may hold more heat than a teakettle full of boiling water.
If the atoms in a molecule share electrons equally, the molecule is said to be non-polar.
Ice floats because water molecules in ice are more tightly packed then in liquid water.
Atoms in a water molecule are held together by the sharing of electrons.
If solution-A has a pH of 2 and solution-B has a pH of 5 then solution-B is a stronger base then solution-A
An atom that has gained or lost electron is called an ion.
Hydrogen bonds are stronger then covalent bonds.
Water is a good solvent in living organisms.
Figure 2.1 The hierarchy of biological order from atom to organism
Table 2.1 0
LE 2-3 Sodium Chlorine Sodium Chloride
Figure 2.5 Two simplified models of a helium (He) atom
LE 2-4a 2 2 2 Protons Neutrons Electrons Helium atom Mass number = 4 6 6 6 Protons Neutrons Electrons Carbon atom Mass number = 12 Electron cloud Nucleus 2e – 6e –
Figure 2.10 Electron configurations of the first 18 elements
Figure 2.12x Methane
Figure 2.12 Covalent bonding in four molecules
LE 2-6b Nitrogen (N) Atomic number = 7 Oxygen (O) Atomic number = 8
LE 2-9 A water molecule
Figure 2.16 A hydrogen bond
Figure 2.15 A sodium chloride crystal
LE 2-7a-1 Transfer of electron Na Sodium atom Cl Chlorine atom
LE 2-7a-2 Na Sodium ion Cl Chloride ion Sodium chloride (NaCl)
LE 2-7b Na Cl
LE 2-10 Hydrogen bond
Figure 2.11 0
LE 2-13 Hydrogen bond Ice Hydrogen bonds are stable Liquid water Hydrogen bonds constantly break and re-form
LE 2-14 Ion in solution Salt crystal
Trees and Water Transport
LE 2-15 Acidic solution OH H H H H OH H H H OH OH OH OH OH H H H H H H Increasingly ACIDIC (Higher concentration of H ) Neutral solution OH OH OH OH OH OH H H Basic solution NEUTRAL H pH scale Lemon juice, gastric juice Grapefruit juice, soft drink Tomato juice Human urine Pure water Human blood Seawater Milk of magnesia Household ammonia Household bleach Oven cleaner Increasingly BASIC (Lower concentration of H )