Acid & Metal Reactions - Acids, Bases & Salts Video Lecture - Class 10 | Best Video for Class 10

at the end of the previous lesson your
task was to prepare salts from the
following reactants sodium carbonate
zinc oxide sodium hydroxide zinc
carbonate hydrochloric acid and sulfuric
acid
let's join John in the lab to see how
some learners managed this time
how many salts did you find I found four
salts me too me too
excellent tell me about them well I got
sodium chloride by reacting sodium
hydroxide with hydrochloric acid but
what about the balanced equation did you
get that part too yes I did tell me
about it in AOH plus HCl good we'll give
me any CL + h2o
that's brilliant
I also got sodium chloride but I use the
different method tell me about the
method you used
well I took hydrochloric acid and mixed
it with sodium carbonate that's a good
method but what about the balanced
equation could you get that part right
here's my answer but I can't balance it
will give it to me anyway it's Nico 3
plus HCl which gave me in a CL plus h2o
plus co2 I see the mistake the formula
for sodium carbonate is not in a co 3
but is in a 2 co 3 that's right
let's fix it that was quite careless of
me I know that sodium ions have a charge
of +1 and carbonate ions have a charge
of minus 2 you're right so now we can
balance the equation quite easily by
placing a 2 in front of the hydrochloric
acid and a 2 in front of the NaCl and
the equation is now balanced now can you
see how we can make sodium sulfate what
method did you try well I added sulfuric
acid to sodium hydroxide and I added
sulfuric acid to sodium carbonate those
are both brilliant methods let's write
down those equations on the board
we'll start with sodium hydroxide plus
sulfuric acid those that will give us
sodium sulfate plus water need to
balance the equation and the other
second method was to take sodium
carbonate plus sulfuric acid
to give us sodium sulfate plus water
plus carbon dioxide and the equations
are balanced that's a very good question
remember we can make zinc salts zinc
chloride and zinc sulfate by the same
two methods we can add an acid plus a
base or an acid plus a carbonates let's
go back to the studio now to check out
those balanced equations to make zinc
chloride we can use one of two methods
one using an oxide and the other using a
carbonate for the first method an acid
plus a base react to form salt plus
water we use hydrochloric acid and zinc
oxide as our base in order to make zinc
chloride our balanced chemical equation
is 2 HCl plus Z n o react to form Z n CL
2 plus h2o and for the method an acid
plus a carbonate react to form salt just
carbon dioxide plus water we use HCl and
zinc carbonate as our base our balanced
chemical equation is 2 HCl plus Z n Co 3
react to form Z n CL 2 plus CO 2 plus
h2o we can prepare zinc sulfate using
the same two methods now I'm sure you'll
agree that this task has given us great
practice in writing equations and I'm
sure you're quite used to using the
different methods to prepare salts but
did you know that there's one other
reaction of acids that can be used to
make salts we have seen it before but in
this lesson we are going to focus on
this reaction
it is the reaction of an acid and a
missile let's take a look at our
outcomes for today by the end of this
lesson you will be able to identify the
products formed when an acid reacts with
a metal and right balanced equations for
salt preparations let's go to the lab to
see how zinc reacts with sulfuric acid
in this test tube I have some zinc
nickel I'm going to add some dilute
sulfuric acid to it but at the same time
I'm getting ready a piece of splint to
test for a gas that may be released
there is a gas being released let's test
it with a splint did you hear it made a
popping sound this confirms that it must
be hydrogen gas now let's see what was
happening in that reaction we added zinc
to sulfuric acid which is it n plus h2
so4 now hydrogen gas was released so we
can write h2 as one of the products so
what is the other product it must be the
salt zinc sulfate with the formula Z n
so4 this gives us the equation Z n plus
h2 so4 react to form Z in so4 plus h2
now we could collect the salt after the
water from the dilute acid has
evaporated what has really happened here
is that the zinc has displaced the
hydrogen from the acid to form a salt
and hydrogen gas now this method is not
often used for salt preparations for
some very
interesting reasons to explain these
reasons let's look at the reactivity
series of metals again potassium sodium
and lithium are very reactive metals the
reaction of an acid with these metals is
not suitable to prepare salts of these
metals lid mercury copper and silver are
all fairly and reactive metals they do
not displace hydrogen from an acid so
you cannot prepare salts of these metals
by reacting the metal and an acid
now when the metals calcium magnesium
aluminium zinc and iron react with acid
they give up some hydrogen and heat but
these reactions are not too dangerous
and can be used as a salt preparation
let's take a look at today's talk
prepare the following salts using the
three methods zinc chloride and
aluminium sulfate now at the top of the
reactivity series we have the Group one
metals potassium sodium and lithium
these metals displace hydrogen from
water so will displace hydrogen from an
acid even more easily these reactions
are violent because they release in lots
of hydrogen and heat the hydrogen can
then react with the oxygen in the air in
an explosion
we cannot safely use this for salt
preparations but as an exciting into
this series let's see if John can end it
off with a bang I've come outside
because the reaction of require nature
is an acid
is extremely dangerous so I've taken
some special safety precautions the
first thing I've done is I've taken some
card and I've attached a very long
string to it then the old plastic
container cut a snit not placed acid in
the bottom of it secured it with some
soil at the bottom over there now I'm
going to place the pod inside to make a
trap door next I'm transferring very
carefully my group 1 metal sodium on to
my trap door just about ready to set
this explosion going
now that's what I call a big bang I hope
you have enjoyed the series on acids
bases and salts remember to check out
the answers to all the tasks on our
website WWE and CCO today this will give
you confidence to know that you can do
really well in this section of work till
we meet again
goodbye