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and sodium hydroxide together to includes only the things that form

form salt and water: products. Second, the total charge
is the same on both sides of the
HCl + NaOH H 2O + NaCl
equation. (If there are three plus
When the hydrochloric acid (HCl) is
signs on one side, then there
in solution, it completely
should be three plus signs on the
dissociates into ions, as does the other.)
sodium hydroxide (NaOH):

+
-
HCl H (aq)+ Cl (aq)
+ - Rates of Reaction
NaOH Na (aq) + OH (aq)
Which leaves the ions to come Chemists want to control not only
together to form water and salt: what comes out of a chemical
reaction, but how fast the reaction
+
-
H (aq) + OH (aq) H 2O (water)
occurs. For example, scientists are
+
-
Cl (aq) + Na (aq) NaCl (salt) working to slow down the depletion
Note: It’s never okay to eat or rate of the ozone in the upper level
of our atmosphere, so we stay
drink anything you use in your
chemistry lab, no matter how safe protected from harmful UV rays.
you think it is! The rate of the chemical reaction of

In a redox reaction, electrons zip a nail rusting is slow compared to
how fast baking soda reacts with
between the two reactants like in
vinegar. Different factors affect the
this example of hydrochloric acid
(HCl) and zinc (Zn): speed of the reaction, but the main
idea is that the more collisions
-
Zn (s) Zn 2+ (aq) + 2e (the zinc is between particles, the faster the
oxidized)
reaction will take place.
+
The H ions of the HCl gain
Increasing the temperature will
electrons and are reduced to H
usually increase the rate of
atoms, which combine to form H 2
reaction, as the higher the
molecules:
temperature of the reactants, the
-
+
2H (aq) + 2e H 2(g) more kinetic energy is in the
system. A general rule is that the
The main equation for the reaction:
rate of reaction will double for
+
Zn (s) + 2H (aq) Zn 2+ (aq) + H 2(g) every 10 C increase in
o
When balancing redox reaction temperature. (Note that if you heat
equations, just keep two important your reactants above a certain
things in mind. First, your equation point, you can actually decrease

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