can someone please help im not gettin science at all!!!?

Question

Balance each chemical reaction by adding the appropriate coefficients: (20K)

a) Cu + O2 --> CuO
b) Al + NiCl2 --> Ni + AlCl3
c) Cl2 + NaBr --> NaCl + Br2
d) Fe + CuF2 --> Cu + FeF3
e) Na + S --> Na2S
f) C5H12 + O2 --> CO2 + H2O
g) HCl + Mg --> MgCl2 + H2
h) NaOH --> Na + O2 + H2
i) Cl2 + KI --> I2 + KCl
j) 3 C + Fe2O3 --> Fe + CO2
When a solution becomes more basic, does the pH increase or decrease? Explain.

Explaining Factors that Affect Rates of Reactions
Factor
-How factor affects the rate of a chemical reaction
-Explanation using collision model

temperature,
concentration of reactants
surface area
catalyst

Answer 1

Yes, getting the hang of chemistry can be a problem, let me give some pointers with balancing equations.
Think of the equations as algebra problems. You have to wind up with the same number of each INDIVIDUAL atom on both sides. If you don't, you can multiply one or more elements or compounds until you do.

(1) Copper metal is oxidized to CuO with O2.
So with ?Cu+?O2 =>? CuO, you need to have two oxygens on both sides (oxygen as a gas occurs as the dimer O=O, so then
? Cu+O2 => 2 CuO. NOW , you need to have 2 coppers on both sides, so change Cu to 2 Cu. Then 2 Cu + O2 => 2 CuO

All these reactions are more or less just variations on this. Lets try d.
? Fe +? CuF2 => ?Cu + ?FeF3. In this reaction, copper in copper (II) fluoride is reduced to metallic copper while iron reacts with the fluoride to form ferric fluoride. The first problem is with fluoride. Since we have 2 on one side and 3 on the other, the best way to balance is to multiply the fluorides on each side by 3 and 2 respectively. Then
?Fe+ 3CuF2 => ?Cu + 2FeF3
Now to balance Fe, we change 1 Fe to 2 Fe, and to balance copper, we change 1 Cu to 3 Cu. Then
2 Fe+ 3 CuF2 => 3 Cu + 2 FeF3.
All the other numbers fall into line
(f) is the hardest. This is the burning of pentane in air. CO2 and H2O are formed.
All the carbon in CO2 comes from pentane, and all the hydrogen in water comes from pentane. So to balance C and H, we write
C5H12 + ? O2 => 5CO2 + 6 H2O.
On the right, we have 18 O. To supply this, we need 9O2 on the left. Soooo.
C5H12 + 9 O2 => 5CO2 + 6 H2O.

With respect to solution pH, pH goes in the OPPOSITE direction as does acidity. A more basic solution is the same as a less acid solution, so the pH increases.

Rate of Reaction. In this model, reactions occur when molecules collide with each other and break the molecule into smaller reacting components. These components can join with others to form new compounds. The RATE of the reaction is how fast this can happen. One obstacle to this is an "energy barrier", or how much energy is needed to break a molecule. If this barrier is too high, the reacting components cannot react with others.

At higher temperature, the molecules move at higher speeds, and collisions are more energetic and molecules can break apart more often. The more reactants means there are more molecules around to collide, so the number of collisions again rises. Catalysts serve to lower the energy barrier.

Answer 2

a) 2Cu + O2 = 2CuO
b) 2Al + 3NiCl2 = 2AlCl3 + 3Ni
c) Cl2 + 2NaBr = 2NaCl + Br2
d) 2Fe + 3CuF2 = 3Cu + 2FeF3
e) 2Na + S = Na2S
f) C5H12 + 8O2 = 5CO2 + 6H2O
g) 2HCl + Mg = MgCl2 + H2
h) 2NaOH = 2Na + O2 + H2
i) Cl2 + 2KI = I2 + 2KCl
j) 3C + 2Fe2O3 = 4Fe +3CO2

pH ranges from 0(zero) to 14 with neutrality at 7
Acid = pH = 0 (Concentrated sulphuric acid)
Neutral = pH = 7 (Water)
Alkalline = pH = 14 (Concentrated sodium hydroxide).

Factors affecting rate of reaction are :-

Temperature : When particles have greater temperature they have more kinetic energy (move around faster). Because they are moving faster there is more chance of a successful collision(reaction).

Concentration : When particles have greater concentration they are more crowded together, in a given volume. Because they are more crowded, there is more chance of a successful collision(reaction)

Surface Area : If a reacting particle is broken down into two or more smaller pieces, there is more surface area, for the two reactants to come together and react.

Catalyst : Provides a surface for reactants to come together and react. It is an alternative route for combining chemicals because it lowers the energy required and speeds up the rate of reaction.

Answer 3

If someone does all your work for you, you will never get it.