Reactions of acids

In a nutshell

Metal oxides / hydroxides / carbonates are alkaline when dissolved in water and when they react with acids. Carbonates produce carbon dioxide when reacted with acid.

Equations

REACtants		PRODUCTS
$acid+metal$	$\rightarrow$	$salt+hydrogen$
$acid\ +\ metal\ oxide$	$\rightarrow$	$salt\ +\ water$
$acid\ +\ metal\ hydroxide$	$\rightarrow$	$salt\ +\ water$
$acid\ +\ metal\ carbonate$	$\rightarrow$	$salt\ +\ water\ +\ carbon\ dioxide$

Acids and metals

When an acid reacts with a metal it produces hydrogen and a salt. The presence of hydrogen can be verified using the 'squeaky pop' test.

Examples

$nitric\ acid\ +\ sodium\ \rightarrow\ sodium\ nitrate\ +\ hydrogen\\\ \\2HNO_3+2Na\rightarrow 2NaNO_3+H_2\\\ \\sulfuric\ acid\ +\ potassium\ \rightarrow\ potassium\ sulfate\ +\ hydrogen\\\ \\H_2SO_4+2K\rightarrow K_2SO_4+H_2$

Naming salts

Salts have two parts to their name. The first part of the name comes from the metal and the second part comes from the acid.

Examples

Sodium sulfate is formed from sodium (metal) and sulfuric acid.
Potassium chloride is formed from potassium (metal) and hydrochloric acid.
Magnesium nitrate is formed from magnesium (metal) and nitric acid.

Acids, metal oxides and metal hydroxides

Some metal oxides and metal hydroxides dissolve in water, these compounds are known as alkalis. They react with acids to undergo a neutralisation reaction and they form a salt and water.

$acid\ +\ metal\ oxide\ \rightarrow\ salt\ +\ water\\\ \\acid\ +\ metal\ hydroxide\ \rightarrow\ salt\ +\ water$

Procedure

1.	The metal from the metal oxide / hydroxide reacts with the negative ion from the acid, $HA\ \rightarrow\ H^+\ +\ A^-$ . The $A^-$ in this case.
2.	If you have done the above step correctly there should be $H^+$ and $OH^-$ left over which forms the water.

Examples

$hydrochloric\ acid\ +\ magnesium\ oxide\ \rightarrow\ magnesium\ chloride\ +\ water\\\ \\2HCl\ +\ MgO\ \rightarrow\ MgCl_{2}\ + \ H_2O\\ \ \\ nitric\ acid\ + \ sodium\ hydroxide\ \rightarrow\ sodium\ nitrate\ +\ water\\ \ \\HNO_3\ +\ NaOH\ \rightarrow\ NaNO_3\ +\ H_2O\\$

Acids and metal carbonates

Reacting an acid with a metal carbonate releases carbon dioxide, as well as producing a salt and water. This reaction is similar to a neutralisation reaction, but with carbon dioxide as the product.

$acid\ +\ metal\ carbonate\ \rightarrow\ salt\ +\ water\ +\ carbon\ dioxide$

Example

$hydrochloric \ acid\ +\ calcium\ carbonate\ \rightarrow\ calcium\ chloride\ +\ water\ +\ carbon\ dioxide\\\ \\2HCl\ +\ CaCO_3\ \rightarrow\ CaCl_2\ +\ H_2O\ +\ CO_2$