Metals and oxygen and metals and water reaction answers

Reactions of metals and metal compounds with acids

1. Metals react with acid to form metal salts and hydrogen gas.

The general equation is:

Metal + acid --> metal salt + hydrogen gas.

example: Magnesium + sulfuric acid --> Magnesium sulfate + hydrogen gas


2. Metal hydroxides and metal oxides react with acids to from metal salts and water.

The general equation is:
Metal hydroxide + acid --> metal salt + water
or metal oxide

example: Lithium hydroxide + nitric acid --> lithium nitrate + water
Sodium oxide + hydrochloric acid --> sodium chloride + water


3. Metal carbonates react with acids to form metal salts and water and carbon dioxide gas.

The gerenal equation is:
Metal carbonate + acid --> metal salt + water + carbon dioxide gas.

example: Lead carbonate + sulfuric acid -->lead sulfate + water + carbon dioxide gas.

Reactions of Metals with oxygen and water

Metals react with oxygen depending on how reactive they are.

This is termed as either burning, oxidation, corrosion or rusting.
The term rusting is for the reaction of iron with oxygen only.

General equation:
Metal + oxygen --> metal oxide
Iron + Oxygen --> iron oxide (rust)


Metals react with water again depending on how reactive they are.

Highly reactive metals react to form metal hydroxides.

General equation:
Metal + water --> metal hydroxide + Hydrogen gas
Sodium + water --> sodium hydroxide + hydrogen gas

Less slows reactive metals will react slowly with HOT water to form metal oxides.

General equation:
Metal + steam --> metal oxide + hydrogen gas
Copper + steam --> copper oxide + hydrogen gas

Neutralisation reactions

Naming salts:

Common acids reacted during neutralisation reaction are:

hydrochloric acid: -HCl salt name: ____________ chloride
Nitric acid: -HNO3 salt name: ____________ nitrate
Sulfuric acid: -H2SO4 salt name: ____________ sulfate


General equations:

metal + acid --> water + salt

calcium + hydrochloric acid --> water + calcium chloride

metal oxide + acid --> water + salt

magnesium oxide + sulfuric acid --> water + magnesium sulfate

metal hydroxide + acid --> water + salt

sodium hydroxide + nitric acid --> water + sodium nitrate

metal carbonate + acid --> water + salt + carbon dioxide gas

calcium carbonate + sulfuric acid --> water + calcium sulfate + carbon dioxide gas

Writing chemical formula

This is done by using the the table of ions.

Take the charge of the ions and drop and swap the numbers.

copper hydroxide: = Cu2+ OH 1-
= Cu1 OH2

= Cu(OH)2

When do I use brackets??

Brackets are used when a number bigger than 1 is placed behind an ion that has two capital letters in its formula. eg OH-.

copper hydroxide = Cu(OH)2 not CuOH2

calcium nitrate = Ca(NO3)2 not CaNO32.

Aluminium sulfate = Al2(SO4)3

Rules for writing chemical equations

When writing chemical equations you MUST follow the following rules.

1. Write a word equation for the reaction.
   
2. Convert the words into symbols using the table of ions.
3. Balance the equation by making a telly of the number of each atom in both sides of the equation.
4. Place large numbers in front of any formula you require more of.
5. Do NOT add and small numbers within a formula when balancing.

Acids and alkalis

Indicators and the pH scale

Litmus Vs Universal indicators.

Litmus only shows whether a substance is an acid or alkali.

Universal indicator also shows whether a substance is an acid or alkali, but also shows the strength of the acid or alkali and gives an indication of the substances pH.

Welcome to year 11 chemistry

This blog is set up as a place where we can put important hints and facts that will hopefully help you when you come to study for exams.