The element names and # of valence electrons for F, Cl, Br, I, At.
What is Fluorine, Chlorine, Bromine, Iodine, and Astatine. They have 7 valence electrons.
100
Balance this equation: H2 + O2 ---> H2O
What is 2H2 + O2 ---> 2H2O
100
The minimum amount of energy needed to start a chemical reaction. Why is it needed? How much is needed?
What is Activation energy. The energy is used to break the chemical bonds of the reactants. Then, the atoms begin to form the new chemical bonds of the products. All chemical reactions need a certain amount of activation energy to get started. Some only need an electric spark.
100
A solution in which more solute may be dissolved.
What is unsaturated solution.
100
The study of compounds that contain carbon
What is organic chemistry
200
The element names and # of valence electrons for Li, Na, K, Rb, Cs, and Fr.
What is Lithium, Sodium, Potassium, Rubidium, Cesium, and Francium. They have 1 valence electron.
200
Balance this: N2 + H2 --> NH3
What is N2 + 3H2 --> 2NH3
200
Name these two materials that oppose each other in their rate of reaction. One material use to increase the rate of reaction and decrease the rate of reaction. Explain how.
What is Catalyst & Inhibitor.
Catalysts are materials that increase the rate of a reaction by lowering the activation energy. Although catalysts affect a reactions's rate, they aren't permanently changed by a reaction. Biological catalysts, or enzymes, decrease the reaction temperature. They provide a surface on which reactions take place. By bringing reactant molecules close together, the enzyme lowers the activation energy needed.
Inhibitors are materials used to decrease the rate of a reaction. Sometimes a reaction is more useful when it can be slowed down rather that sped up. Most inhibitors work by preventing reactants from coming together. Usually they combine with one of the reactants, either permanently, or temporarily.
200
Describe at least two differences between a dilute solution and a concentrated solution of sugar water.
What is concentrated solution...
tastes sweeter,
has more sugar dissolved in the same volume of water,
has a lower freezing point,
has a higher boiling point.
200
Organic molecules consisting of only CARBON and HYDROGEN.
What is hydrocarbons
300
The element names and # of valence electrons for C, Si, Ge, Sn, Pb.
What is Carbon, Silicon, Germanium, Tin, and Lead. They have 4 valence electrons.
300
Name the following types of reactions in order
AB + CD → AD + CB
A+B = AB
AB = A+B
What is replacement, synthesis, decomposition
300
One is increases reaction rate by heating particles. The other increases the reaction rate by increasing the amount of the substance.
What is temperature and concentration.
Temperature is a way to increase the reaction speed. When you heat a substance, the particles move faster. Faster-moving particles increase the reaction rate in two ways. First, the particles come in contact more often, which means there are more chances for a reaction to happen. Second, faster-moving particles have more energy. This increased energy causes more particles of the reactants to get over the activation energy "hump."
Concentration is the amount of a substance in a given volume. It increases the rate of the reaction. It supplies more particles to react. The reaction is slower with less concentration then with more.
300
The concentration of an alcohol and water solution is 25% alcohol by volume. What is the volume of alcohol in 200 mL of the solution?
What is 50mL
300
For what reason do unsaturated hydrocarbons must have a minimum of two carbons
What is they have at least a double or triple bond that needs to be formed between two carbon atoms.
400
The element names and # of valence electrons for He, Ne, Ar, Kr, Xe, Rn.
What is Helium, Neon, Argon, Krypton, Xenon, Radon. They have 8 valence electrons.
400
Al + Fe2O3 --> Al2O3 + Fe
What is 2Al + Fe2O3 --> Al2O3 + 2Fe
400
How do you change the rate of a reaction with its surface area?
What is When a chunk of solid substance reacts with a liquid or gas, only the particles on the surface of the solid come into contact with the other reactant. But if you break the solid into smaller pieces, more particles are exposed and the reaction happens faster. Sometimes, speeding up a reaction this way is dangerous. Other times, increasing surface area can be useful.
400
You can dilute a 60 mL can of fruit punch with enough water to make a total of 300mL. What is the concentration of juice in percent by volume in the final mixture?
What is 20%
400
Example of a polymer made by a living thing?
What is wool from sheep, cotton from cotton plants, silk from silkworms.
500
The element names and # of valence electrons for Cr, Fe, Co, Ni, Cu, Zn, Ag, Au, Pt, Hg.
What is chromium, iron, cobalt, nickel, copper, zinc, silver, gold, platinum, mercury. They have 3 valence electrons.
500
Balance: C4H10 + O2 --> H2O +CO2
What is 2C4H10 + 13O2 --> 10H2O + 8CO2
500
Compare endothermic and exothermic reactions.
What is...
Exothermic reactions need activation energy to get started. At the end of the reaction, the the products have less energy than the reactants. Examples are burning fuel, such as wood, natural gas, or oil.
Endothermic reactions also need activation energy, but they need it throughout the entire reaction. The energy of the products is higher than that of the reactants. The reaction must absorb energy to continue. Examples are the reaction of vinegar and baking soda.
Every chemical reaction needs activation energy to get it started. Whether or not a reaction needs still more energy from the environment to keep going depends on if it is exothermic or endothermic.
500
Explain how an indicator helps you distinguish between an acid and a base.
What is it has a different color in an acid than it does in a base.
500
Name the following as a hydrocarbon, alcohol, organic acid, or halogen compound.
C12H20COOH
C7H16
C2H5Cl
C4H7OH
What is organic acid, hydrocarbon, halogen compound, and alcohol.