Topic 4 Acids and alkalis Flashcards Preview

Edexcel GCSE Combined Science (Chemistry) > Topic 4 Acids and alkalis > Flashcards

Flashcards in Topic 4 Acids and alkalis Deck (70)
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1
Q
  1. What term describes a substance that attacks metals, stonework and skin?
A

corrosive

2
Q
  1. Name an acidic solution found in the kitchen.
A

vinegar or fruit juice, etc.

3
Q
  1. Name an alkaline solution used in the kitchen.
A

bleach or oven cleaner or soap, etc.

4
Q
  1. What type of substance turns litmus paper red?
A

acid

5
Q
  1. How does an indicator show the acidity or alkalinity of solutions?
A

by changing colour

6
Q
  1. What pH values represent alkaline solutions?
A

above 7 or 8 to 14

7
Q
  1. What happens in all chemical reactions?
A

new substances are formed

8
Q
  1. What kind of reaction occurs between an acid and an alkali?
A

neutralisation

9
Q
  1. What do you call a solution that is neither acidic nor alkaline.
A

neutral

10
Q
  1. Give the name and formula of a common laboratory acid.
A

hydrochloric acid (HCl) or nitric acid (HNO3) or sulfuric acid (H2SO4), etc.

11
Q
  1. Which ion is in excess in all acidic solutions?
A

hydrogen ions or H+ ions

12
Q
  1. Which ion is in excess in all alkaline solutions?
A

hydroxide ions or OH ions

13
Q
  1. What scale is used for measuring acidic and alkaline properties?
A

the pH scale

14
Q
  1. Name three examples of acid/alkali indicators apart from universal indicator.
A

litmus, methyl orange and phenolphthalein

15
Q
  1. What would you use to measure pH to one decimal place?
A

a pH meter

16
Q
  1. What pH values are acidic?
A

below 7

17
Q
  1. What colour is phenolphthalein in a solution with a pH of 2?
A

colourless

18
Q
  1. What happens to the pH as the H+ ion concentration increases?
A

it decreases

19
Q
  1. If a solution has the same concentration of hydrogen ions as hydroxide ions, how is it described?
A

neutral or pH = 7

20
Q
  1. If 2 g of salt is dissolved in 250 cm3 of solution, what is its concentration in g dm–3?
A

8 g dm–3

21
Q
  1. What word describes a solution that contains a large amount of solute in a small volume of solvent?
A

concentrated

22
Q
  1. How can a solution be made more dilute?
A

by adding solvent/water

23
Q
  1. If 24 g of acid is dissolved in 600 cm3 of solution, what is its concentration in g dm–3?
A

40 g dm–3

24
Q
  1. What happens when strong acid molecules dissolve in water?
A

they dissociate completely into ions

25
Q
  1. What kind of reaction occurs between an acid and a base?
A

neutralisation

26
Q
  1. What happens to the pH of an acid as it reacts with a neutraliser?
A

pH increases

27
Q
  1. What is formed when an acid reacts with a base like a metal oxide?
A

salt + water

28
Q
  1. What acid would be used to make zinc sulfate from zinc oxide?
A

sulfuric acid (sulphuric acid makes sulphates!)

29
Q
  1. What process can be used to separate an insoluble solid from a liquid?
A

filtration

30
Q
  1. How can a sample of a dissolved salt be obtained from a salt solution?
A

evaporation of the water

31
Q
  1. In general, what is the pH of an alkaline solution?
A

greater than 7

32
Q
  1. Which ions, hydrogen ions or hydroxide ions, are released by alkalis in solution?
A

hydroxide ions (OH-)

33
Q
  1. What colour is litmus solution in acidic solutions?
A

red

34
Q
  1. What name is given to substances that react with acids to form a salt and water only?
A

bases (bases are metal oxides and hydroxides, soluble bases are alkalis)

35
Q
  1. Which salt is formed when copper oxide reacts with sulfuric acid?
A

copper sulfate

36
Q
  1. What type of reaction happens between an acid and a base?
A

neutralisation

37
Q
  1. What type of solution has a pH of 7?
A

neutral

38
Q
  1. Name the acid that has the formula HCl.
A

hydrochloric acid

39
Q
  1. What colour is phenolphthalein in alkaline solutions?
A

pink (it is colourless in acid conditions)

40
Q
  1. What is the formula for sulfuric acid?
A

H2SO4

41
Q
  1. Name the salt produced when sodium hydroxide reacts with hydrochloric acid.
A

sodium chloride

42
Q
  1. Which ions, hydrogen ions or hydroxide ions, are released by acids in solution?
A

hydrogen ions (H+)

43
Q
  1. What substance, other than a salt, is produced when an alkali neutralises an acid?
A

water

44
Q
  1. What name is given to substances that are soluble bases?
A

alkalis

45
Q
  1. What is the formula for hydrochloric acid?
A

HCl

46
Q
  1. What type of solution has a pH above 7?
A

alkaline

47
Q
  1. What colour is phenolphthalein in acidic solutions?
A

colourless – not ‘clear’

48
Q
  1. Name a piece of apparatus used to measure volumes of liquid.
A

measuring cylinder/pipette/burette

49
Q
  1. Name the separation method used to produce crystals from a solution.
A

crystallisation

50
Q
  1. Name the acid needed to make ammonium nitrate.
A

nitric acid

51
Q
  1. Which acid can be used to make copper sulfate?
A

sulfuric acid

52
Q
  1. Which base can be used to make copper sulfate?
A

copper oxide

53
Q
  1. Which substance is needed to complete the general equation: acid + base makes salt + …?
A

water (BASHO)

54
Q
  1. What is the formula of nitric acid?
A

HNO3

55
Q
  1. What is the name of the salt formed from zinc oxide and hydrochloric acid?
A

zinc chloride

56
Q
  1. What is the formula of the salt formed from calcium oxide and hydrochloric acid?
A

CaCl2

57
Q
  1. Which ions are present in large quantities in aqueous solutions of all acids?
A

H+ Hydrogen ions

58
Q
  1. Which ions are present in large quantities in aqueous solutions of all alkalis?
A

OH Hydroxide ions

59
Q
  1. Which gas is formed when dilute hydrochloric acid reacts with magnesium?
A

hydrogen (MASH)

60
Q
  1. Which gas is formed when dilute hydrochloric acid reacts with magnesium carbonate?
A

carbon dioxide (CASHOCO)

61
Q
  1. What acid can be used to make copper chloride?
A

hydrochloric acid (hydrochloric acid makes chlorides)

62
Q
  1. What gas is given off when magnesium reacts with dilute sulfuric acid?
A

hydrogen (MASH)

63
Q
  1. How do you identify Hydrogen gas?
A

gives a squeaky pop with a lighted splint

64
Q
  1. What is seen when magnesium is added to dilute sulfuric acid?
A

effervescence/fizzing/bubbles (yes you know this is hydrogen, but you can not see that!!)

65
Q
  1. What is the formula of magnesium sulfate?
A

MgSO4

66
Q
  1. What gas is produced when copper carbonate is added to dilute nitric acid?
A

carbon dioxide (CASHOCO)

67
Q
  1. How do you test for Carbon Dioxide?
A

it turns limewater milky

68
Q
  1. What is the formula of the salt produced when copper carbonate reacts with nitric acid?
A

(Cu(NO3)2)

69
Q
  1. Sodium chloride dissolves in water to form a solution. Which is the solute?
A

sodium chloride

70
Q
  1. What do we call the liquid that dissolves a solute to form a solution.
A

solvent