Chapter 1 fill-in-the-blanks worksheet

If an ion has more _____________________ than protons then it will be a type of a _____________________ ion. If it has less _______________________ than protons then it will be a type of a ______________________ion.

All ions of the same element will have the same number of _____________ but will have different number of _____________________ than each other.

All isotopes of the same element will have the same number of ______________ but will have different number of ______________________ than each other.

Some isotopes are unstable, these will ____________________. They will lose mass in the form of energy ( E = mc2 ). These isotopes are ___________________.

The atomic weight of an element is the mass of the most common isotope of an element.

Chemical bonds, or just bonds form between valance or ________________ electrons of atoms. When atoms bond together they form _____________________. A molecule is the __________________________ unit of a substance that has________________________________ _____________________________________________ of that substance. Is a drop of water, a molecule of water? ______________ How many atoms are there in ONE water molecule?____________________. Which are they? _______________________.

Remember, atoms want their valance electron clouds/orbitals to be completely filled. So they will either try to gain or lose electrons to do so. When electrons are shared between atoms it is a ___________________________ bond. “Co” means to share. If the sharing is uneven, we say it is a polar molecule. The part of the molecule that isn’t getting to share the electrons as much will be slightly _____________________, while the portion that has more of the electrons will be slightly _______________________. The chemical bonds that hold together a living organism’s molecules are usually covalent.

When electrons are given or transferred it is a __________________________ bond. When atoms gain or lose an electron, they become an _______________.

Another type of bond is a hydrogen bond. They only form between a hydrogen atom and either a nitrogen or oxygen atom. They are very weak. They make water a liquid even at relatively cool temperatures. They also help to hold together the two strands of the DNA molecule.

pH Scale

In a solution a certain number of molecules will have ionized/dissociated usually producing ________________/protons and/or ____________________or hydroxyls. We measure these concentrations using the pH scale. H for the hydrogen ion or proton. The scale goes from a pH of 0 to a pH of 14.

Each number represents a concentration of protons as a negative power of 10. A pH 1 represents 10-1 or .1 units of H+. The pH numbers of protons and hydroxyls will always add up to equal a negative 14. The smaller the number, the smaller a negative exponent, the larger the number the larger the negative exponent. A pH of 2 means there are ___________________ or .01 units of protons and _________________ of hydroxyls or ,000000000001. Which are there more of? ______________________. How about a pH of 4? There will be _______________________________ of protons and _____________________________of hydroxyls. A pH of 7? ______________________protons and _____________________ of hydroxyls.

Solutions that have more protons than hydroxyls are said to be acidic, those that have more hydroxyls than protons are basic or alkaline. What is a pH of 5? ________________ a pH of 12? ___________________. Which pH will have the same amount or be neutral?_____________(remember the sum of the two exponents must equal -14).

How many times stronger is an acid with a pH of 3 than one with a pH 5? _______________ (Hint: When you divide with exponents you can just subtract them. So 5 - 3 = 2, so it will be 10 2 or 100 times stronger! How much weaker of an acid is a pH 6 than a pH 2?___________________ .

Chemical reactions, the making and/or breaking of chemical bonds are affected by pH. This is especially true for biochemical reactions (the chemical reactions of living things). For example most of your chemical reactions, and that is the only thing your cells do, will only work within a pH range of 7.2 -7.6.

Remember chemical reactions are simply the making and breaking of chemical bonds. We think this happens because atoms collide together. The amount of energy it takes to cause a collision powerful enough to make or break bonds is called the ACTIVATION ENERGY. The amount of activation energy depends on what type of reaction is occurring. We will learn more about the molecule organisms break apart for this energy. The molecule is called ATP. It is a type of nucleotide.

In a molecular formula, there are two types of numbers; coefficients and subscripts. What do coefficients tell you? __________________________________ and what do subscripts tell you? ____________________________________. Using the correct terms, write three glucose molecules. The molecular formula for one glucose is C6H12O6.

_______________________________

How many total carbon atoms were there? ________________, hydrogen atoms? ________ and oxygen atoms? _____________.

When molecules contain only one kind of atom, it is an ____________________. There is a periodic chart of the elements. When a molecule contains more than one kind of atom it is a _____________________. Hydrogen gas is _________________________ and water is _______________________________.

Molecules are also classified as being organic or inorganic.

Inorganic molecules do NOT contain carbon and hydrogen. Inorganic molecules are often, but not always ionicly bonded.

Organic molecules do contain at least carbon and hydrogen and are covalently bonded. Is water organic or inorganic? ________________________. How about glucose? ____________________.

There are usually just six elements found in organic compounds. Some have all six, others have just the two defining elements, carbon and hydrogen. The six elements are C, H, O, N, P and S. You can remember those as a pretend word CHONPS. You might have to look up on the periodic table what these letters stand for.

If you know the number of electrons needed to fill an atom’s valance shell you will also know the usual number of covalent bonds that atom will make. Remember that each covalent bond is a pair of shared electrons, so each bond represents a temporary gain of one electron. The most common atoms/elements you will encounter in this chapter will be C, N, O and H.

Determine the number of potential covalent bonds for each. C_______, N ______, O ________ and H ___________.Why did I put them in that order?

In organic chemistry it is customary to write some structural formulas using chemical abbreviations. Look at page no.35 fig 1.17 (a), look at the glucose ring drawing. The editors have taken a shortcut and not included all of the C’s. It is “understood” that every unnamed vertex/corner represents a C or carbon. Knowing this, confirm that the diagram has the six carbons that the glucose molecule should. In fact some times the glucose or any other ring compounds are shown by just drawing the overall shape of the molecule. See page no. 36 figu.1.18 (c)and look at how they have depicted the polysaccharide glycogen.

On the same diagram, confirm that our bonding numbers are also working. Count the number of covalent bonds for C, O and H. You will also have noticed now that there is another common abbreviation, hydroxyls can be written without showing the single covalent bond between the O and the H. -OH is the same as the more correct -O-H.

Organisms are mainly made of organic compounds. There are four main types of organic compounds. This is a huge concept, there are four main types of organic compounds.

These four types are: Carbohydrates,Lipids, Proteins and Nucleic Acids.

You should know the following about several of these types: their elements, the smaller molecules/building blocks/monomers of these larger macromolecules or polymers and their primary function in organisms.

Monomers are bonded together forming a polymer, like beads on a necklace. The sequence, type and number of these monomers will determine the characteristics of their assembled polymers. Different beads, different necklace! All organisms use the same monomers but not in the same sequence etc. Your organic compounds/polymers will be slightly different from other organism’s organic compounds because of these different order or sequences. Ultimately the differenct sequences are determined by your genes.

Carbohydrates. See page no. 34

elements:

monomers and functions:

polymers and functions:

Calories/gram:

Lipids. See page no. 35

elements:

polymers and functions: See page no. 36

Calories/gram:

Proteins. See page no. 37

elements:

monomers:

polymers and functions:

1.

2.

3.

4.

5.

6.

Calories/gram:

Nucleic Acids. See page no. 40

elements:

monomers:

Nucleic Acids cont.

polymers and functions:

Calories/gram: Usually not given

Organisms build polymers by bonding lots of monomers together. They always use the following method.

They remove a hydrogen ion or ___________________from one monomer and a OH- or ______________________from another. Without those parts the monomers bond to each other and the removed atoms form a molecule of water.

This is called a dehydration synthesis (dehydration - removing water,

synthesis - building ). Remember this is just like adding beads to form a necklace, except a water molecule must first be removed before the beads will snap together. Again, all biochemical building reactions are DEHYDRATION SYNTHESIS. See page no.36 fig. 1.18 (a), p. 37 fig. 1.19 reading right to left, p. 39 fig. 1.22 (a) and your powerpoint handout.

To digest or break a polymer down into its monomers, organisms do the opposite. They add a proton and a hydroxyl to two consecutive monomers and a bond will be broken.

This is called a hydrolysis reaction or hydrolytic reaction (hydro - water,

lysis - splitting). Remember this is just like snapping a necklace apart into its different beads by adding a water molecule. Again, all biochemical digestive or breaking down reactions are HYDROLYTIC. See page no.37 fig.1.19 reading left to right and your handout.

So, to build polymers such as a protein, you eat. Then using digestive enzymes and activation energy the food proteins (chicken, fish, bean, etc.) are digested (hydrolyzed) into their individual amino acids. The amino acids are then assembled (dehydration synthesis) into the correct sequence and numbers to be your type of protein. The same is true for the other types of organic compounds.

Your cells know these “recipes” of how correctly build/assemble the proteins because of your genes. These digestive and synthesis reactions must be done in the correct pH and temperature for your enzymes or these reactions can not occur.

You must have an ample supply of stored carbohydrates and/or lipids for the simple sugars (usually glucose) or lipids which can be converted to carbohydrates which are used to make more ATP molecules for the activation energy to cause almost ALL biochemical reactions.