Science Revision

Total Internal Reflection occurs when light meets a less dense medium at an angle of incidence larger than the __________.

critical angle

The angle of incidence which causes the angle of reflection to be __________ degrees is known as the critical angle.

90

In the Benedict Test for reducing sugars, the original colour is __________ and a positive test shows __________.

blue; orange/brick red

In the Iodine Test for starch, the original colour is __________ and a positive test shows __________.

orange/brown; blue/black

The original colour of the Biuret Test for protein is __________ and a positive test turns __________.

blue; violet/purple

For lipids, the Ethanol Test shows cloudy __________ forming upon a positive result.

emulsification

An acid has a pH of less than __________.

7

A salt is formed when the metal ions replace the __________ ions in an acid.

hydrogen

Only metals that are above __________ in the reactivity series will react with dilute acids.

hydrogen

When a dilute acid reacts with a metal, a __________ and __________ are formed.

salt; hydrogen

Neutralisation occurs when an acid and __________ react together.

base

When an acid reacts with a metal oxide, __________ and __________ are formed.

salt; water

When an acid reacts with a metal hydroxide, __________ and __________ are formed.

salt; water

When an acid reacts with a metal carbonate, a __________, water, and __________ are formed.

salt; carbon dioxide

Acid turns blue litmus __________.

red

When an acid is added, methyl orange turns __________.

red

Aqueous solutions of acids contain __________ ions.

H+

Aqueous solutions of alkalis contain __________ ions.

OH-

On the pH scale, 0 is very __________ and 14 is very __________.

acidic; alkaline

Acids have a high concentration of __________ ions.

hydrogen

Alkalis have a __________ concentration of hydrogen ions.

low

Neutral solutions have a pH of __________.

7

Yellow, orange, or red colours from a universal indicator indicate ______________.

acidity

Blue or violet colours from a universal indicator indicate ______________.

alkalinity

Neutral solutions will show as __________ using a universal indicator.

green

Acids are known as __________ since they release hydrogen ions.

proton donors

Bases are known as __________ since they accept hydrogen ions.

proton acceptors

A strong acid completely __________ in aqueous solution.

dissociates

A weak acid is an acid that only __________ dissociates in aqueous solution.

partially

HCl is known as a __________ acid.

strong

Ethanoic acid is known as a __________ acid.

weak