acids, alkalis and salts Flashcards
what is the Ph of the stongest acid
0
what is the Ph of the strogest alkali
14
what is the Ph of a neutral substance
7
name the 4 main indicators
univeral indictor, phenophthalein, litmus paper and methyl orange
describe univeral indiactor
uses a wide range of colours to give accurate reading
describe litmus paper indicator
tests if a solution is neutral, acidic or alkaline. red in acid , purple in neutral and blue in alkaline solution s
describe phenophthalein solution
changes from colurless in acid colutions to bright pink in alkaline solutions
what is an acid
a source of h+ (hyrdogen) ions . They are proton donors
what is a base
a substrate that can neutralise acid. It is a proton acceptor
what are alkalies
soluble bases a source of hyrdoxide ions (OH-0
what is the ractione between an acid and a base called
neutralisation
ionic equation for neutralisation
H+(aq)+OH-(aq)–>H2O(l)
what can acids react with
metals, metal oxides and metal carbonates
what form when a acid and base react
salt+water
what type of salt does hydrochloric acid produse
chlorides
what type of salt does sulfuric acid produce
sulfates
what type of salt does nitric acid produce
nitrates
what is formed when acid and metal oxide react
salt+water
what is formed when acid and metal hydroxide react
salt+water
what is formed when acid and ammonia react
ammonia salt
what is formed when an acid and metal carbonate react
slalt+water+carbon doxide
what does a tritation do
allows you to find out how much acid it needed to neutralise and alkali (or vise versa)
how do you carry out tritation
using a pippete and pippert filler add some alkali(25cm3) to a conical flask and with 3 drops of thenothphalein indicator. Fill a biruette with acid, make sure you do this below eye level. Using the burette add the acid to the alkaline a bit at a time and give the conical flask a regular swirl, go slower towards the end point. Record the reading and repeat to get co coordinate results
how do you work out number of moles
concentration*volume
are common salts of sodium,pottasium and ammonia soluble or insoluble
soluble
are all nitrates soluble or insoluble
soluble
are common chlorides soluble or insoluble
all are soluble except sliver chloride and lead chloride
are common sulfates oluble or insoluble
insoluble execpt sodium potassium and ammonium sulfate
are common hydroxides soluble or insoluble
insoluble exexpt sodium pottasium and calcium
whar reaction do you use to get a pure dry sample of a insoluble salt
precipitation reaction
how do you make lead sulfate (insoluble)
add one spatula of lead nitrate to a test tube with deionised water to dissolve it.Then in a seperate test tube do the same with magnesium sulfate. Then tip the 2 solutions into a beaker and stir , a lead sulfate precipitate should form, pour contents into filter paper and scrape out precipitate
how do you make soluble salts
reacting an acid that contains one of the ions you want in a salt with an insoluble base that contains the other ion you need.( Often a metal hydroxide or metal oxide) Start by heating up the acid in a hot water bath , then add the base to the acid, the base and acid will then react to form a soluble salt(and water). Filter the exexs solid sp only the salt andwater is left. Heat the solution to remove some of the water.
how do you make insoluable salts
to make insoluable salts you need to use the precipitation method - pick the 2 right soluble salts and mix them together to get an isoluable salt e.g to make lead sulfate (insoluble) mix lead nitrate and magnesium sulfate (both soluble)
how do you make soluble salts using an acid and alkali
First you do a tritation to work out how much alkali is needed to neutralise the acid. Then do the same as a tritation but with no indicator and slowly evaporate off some of the watet to leave crytals
