Acids and bases, preparation of salts Flashcards
(28 cards)
What is the balanced equation for the reaction between magnesium and dilute sulfuric acid?
A. Mg + H2SO4 → MgSO4 + H2
B. Mg + 2H2SO4 → Mg(SO4)2 + 2H2
C. 2Mg + H2SO4 → Mg2SO4 + H2
D . 2Mg + 3H2SO4 → Mg2(SO4)3 + 3H2
A
Compound X dissolves in water to form an aqueous solution.
Methyl orange is added to aqueous compound X.
The methyl orange turns red.
What is compound X?
A sodium carbonate
B copper(II) oxide
C potassium oxide
D sulfur dioxide
D
Dilute hydrochloric acid reacts with aqueous sodium hydroxide in a neutralisation reaction.
Which two ions are involved in this neutralisation reaction?
A Na+ and H+
B H+ and OH–
C Na+ and Cl–
D OH– and Cl–
B
Which equation represents the neutralisation of nitric acid using sodium hydroxide?
A. NaOH(aq) + HNO3(aq) → NaNO3(aq) + H2O(l)
B NaOH(aq) + HNO3(aq) → NaNO3(l) + H2O(l)
C NaOH(l) + HNO3(l) → NaNO3(l) + H2O(aq)
D NaOH(l) + HNO3(l) → NaNO3(l) + H2O(l)
A
Sodium hydroxide forms an alkaline solution with a pH of 14.
Which indicator turns yellow when added to this solution?
A litmus
B methyl orange
C thymolphthalein
D universal indicator
B
Which solids react with dilute sulfuric acid to form aqueous magnesium sulfate?
1 magnesium
2 magnesium hydroxide
3 magnesium nitrate
4 magnesium oxide
A 1, 2 and 4
B 1 and 3
C 2, 3 and 4
D 2 and 4 only
D
Which statements about an aqueous acid are correct?
1 Ammonia is formed when solid ammonium nitrate is added to an aqueous acid.
2 Effervescence is seen when sodium carbonate is added to an aqueous acid.
3 Methyl orange becomes yellow when added to an aqueous acid.
4 Red litmus remains red when added to an aqueous acid.
A 1 and 3
B 1 and 4
C 2 and 3
D 2 and 4
D
Farmers spread calcium hydroxide on their fields to neutralise soils that are too acidic for crops to grow well.
Which ion neutralises the acid in the soil?
A Ca2+
B H+
C O2–
D OH–
D
Four different solutions, J, K, L and M, are tested with universal indicator.
Solution colours: J green, K red, L purple, M orange
Which solutions are acidic?
A J and M
B K and M
C K only
D L only
B
Methyl orange is added to dilute hydrochloric acid and to aqueous sodium hydroxide.
What is the colour of the methyl orange in each solution?
Colour in dilute hydrochloric acid / Colour in aqueous sodium hydroxide
A orange / red
B red / yellow
C red / orange
D yellow / red
C
Which products are formed when magnesium hydroxide reacts with hydrochloric acid?
A magnesium chloride, carbon dioxide and water
B magnesium chloride, hydrogen and water
C magnesium chloride and hydrogen only
D magnesium chloride and water only
D
Which row about aqueous ethanoic acid and dilute hydrochloric acid is correct?
Both contain carbon / Both contain hydrogen / Both react with carbonates
A Yes / Yes / Yes
B Yes / Yes / No
C Yes / No / Yes
D Yes / No / No
C
When an acid is added to an alkali, the temperature of the reaction mixture rises.
Which words describe this reaction?
A decomposition and endothermic
B decomposition and exothermic
C neutralisation and endothermic
D neutralisation and exothermic
D
Which reaction produces ammonia gas?
A warming ammonium chloride with dilute sodium hydroxide
B warming ammonium nitrate with dilute sulfuric acid
C warming ammonium phosphate with dilute sodium chloride
D warming ammonium sulfate with dilute nitric acid
A
Which reactions produce carbon dioxide?
1 addition of dilute nitric acid to copper(II) carbonate
2 heating zinc carbonate
3 combustion of methane
A 1, 2 and 3
B 1 and 2 only
C 1 and 3 only
D 3 only
B
Hydrogen iodide is dissolved in water. HI → H+ + I–
Which row describes the final colours seen when the solution is tested with damp red litmus paper and with acidified aqueous potassium manganate(VII)?
Litmus / Potassium manganate(VII)
A brown / blue
B colourless / blue
C brown / red
D colourless / red
B
Which statement describes the properties of hydrochloric acid?
A Carbon dioxide is produced when limestone reacts with hydrochloric acid.
B Hydrogen is produced when sodium hydroxide reacts with hydrochloric acid.
C Methyl orange turns yellow in strong hydrochloric acid.
D Red litmus paper turns blue when dipped into hydrochloric acid.
A
Butanoic acid partially dissociates in aqueous solution.
Which row about butanoic acid is correct?
pH effect on thymolphthalein: turns …?
A turns blue / stays blue
B turns blue / turns colourless
C turns colourless / stays blue
D turns colourless / turns colourless
B
The concentration of hydrogen ions in 100 cm3 of 0.1 mol/dm3 hydrochloric acid is higher than in 100 cm3 of 0.1 mol/dm3 ethanoic acid.
Which statement explains the difference?
A Ethanoic acid is an organic acid.
B Ethanoic acid has a lower pH than hydrochloric acid.
C Ethanoic acid is partially dissociated.
D Ethanoic acid is a strong acid.
C
Which gas is made when powdered zinc is added to dilute hydrochloric acid?
A carbon dioxide
B chlorine
C hydrogen
D oxygen
C
Which statement about acids is correct?
A A weak acid partially dissociates in aqueous solution.
B An acid accepts protons when added to water.
C Ethanoic acid acts as a strong acid when added to water.
D Hydrochloric acid is a strong acid that ionises in water to form H– ions.
A
Four different solutions, J, K, L and M, are tested with universal indicator.
Solution colours: J green, K red, L purple, M orange
Which solutions are acidic?
A J and M
B K and M
C K only
D L only
B
Which solution has the lowest pH?
A 0.1 mol/dm3 ammonia solution
B 0.1 mol/dm3 ethanoic acid
C 0.1 mol/dm3 hydrochloric acid
D 0.1 mol/dm3 lithium hydroxide
C
Methyl orange is added to dilute hydrochloric acid and to aqueous sodium hydroxide.
What is the colour of the methyl orange in each solution?
Colour in dilute hydrochloric acid / Colour in aqueous sodium hydroxide
A orange / red
B red / yellow
C red / orange
D yellow / red
C
