Chemical Changes and Structures Flashcards Preview

National 5 Chemistry - Nature's Chemistry > Chemical Changes and Structures > Flashcards

Flashcards in Chemical Changes and Structures Deck (29)
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1
Q

What is the pH scale a measure of?

A

The concentration of hydrogen ions in a substance

2
Q

What is a neutral solution?

A

A solution with the same concentration of hydrogen and hydroxide ions

3
Q

What is the pH of a neutral solution?

A

7

4
Q

What is the pH of an acidic solution?

A

Less than 7

5
Q

What is the pH of an alkaline solution?

A

More than 7

6
Q

Does an alkaline solution have a higher concentration of hydrogen or hydroxide ions?

A

hydroxide ions

7
Q

How will the dilution of an acidic solution affect the pH?

A

It will increase the pH, bringing it closer to 7

8
Q

How will the dilution of an alkaline solution affect the pH?

A

It will decrease the pH, bringing it closer to 7

9
Q

What is dissolved in water to form an acidic solution?

A

non-metal oxides

10
Q

What is the word equation for the formation of an acid?

A

non-metal oxide + water –> acid

11
Q

What is the word equation for the formation of a metal hydroxide?

A

metal oxide + water –> metal hydroxide

12
Q

What is a neutralisation reaction?

A

A reaction in which a metal oxide reacts with an acid to make water and a salt

13
Q

What is the word equation for a neutralisation reaction?

A

metal oxide + acid –> water + salt

14
Q

What is produced when a metal carbonate reacts with and acid

A

a salt, water and carbon dioxide

15
Q

What is the word equation for the reaction between a metal carbonate and an acid?

A

metal carbonate + acid –> salt + water + carbon dioxide

16
Q

what is the word equation for the reaction between a metal and an acid?

A

metal + acid –> salt + hydrogen

17
Q

How is a salt named?

A

the first part is named from the the metal in the base that was used
the second part comes from the acid used

18
Q

What are the factors affecting rate of reaction?

A
  • temperature
  • concentration
  • particle size/surface area
  • use of a catalyst
19
Q

What is a catalyst?

A

a substance that speeds up a chemical reaction and remain unchanged by the reaction

20
Q

How are elements in the periodic table arranged?

A

In order of increasing atomic number

21
Q

What are covalent bonds?

A

a bond formed between two non-metal atoms formed when two positive nuclei are held together by their attraction for a shared pair of electrons

22
Q

What are the diatomic elements?

A

Hydrogen, Nitrogen, Florine, Oxygen, Iodine, Chlorine and Bromine

23
Q

What are the properties of a covalent molecular substance?

A
  • they have strong covalent bonds with molecules and weak attraction between the molecules
  • have low melting and boiling points
  • do not conduct electricity because their electrons are not free to move
24
Q

What are the properties of covalent network structures?

A
  • have a network of strong covalent bonds within one giant structure
  • have very high melting and boiling points
  • do not dissolve
25
Q

How are ions formed?

A

when atoms lose or gain electrons to become stable

26
Q

What are ionic bonds?

A

the electrostatic attraction between positive and negative ions

27
Q

Why do ionic compounds have high melting and boiling points?

A

Because strong ionic bonds must be broken

28
Q

When do ionic compounds conduct electricity?

A

when molten or in solution

29
Q

What is the valency of the noble gases?

A

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