Theory

CH20 - NITROGEN COMPOUNDS

Oxygen is a Group 16 element. (a) (i) Write equations for the following reactions. • sodium and oxygen • sulfur and oxygen $\text{.............

2024 Winter

3

Theory

CH20 - NITROGEN COMPOUNDS

(a) Nitrogen is found in inorganic compounds such as nitrogen oxides (NO\(_x\)), nitrates and nitric acid.(i) Identify one natural and one man-made oc...

2024 Winter

3

Theory

CH20 - NITROGEN COMPOUNDS

(a) \( NH_3(g) \) reacts with \( HCl(g) \) to produce \( NH_4Cl(s) \), as shown.\[ NH_3(g) + HCl(g) \rightarrow NH_4Cl(s) \]Draw a diagram to show the...

2024 Summer

2

Theory

CH20 - NITROGEN COMPOUNDS

Nitrogen, $N_2$, is generally an unreactive molecule but it does react under certain conditions. (a) Give two reasons to explain the lack of reactivi...

2024 Spring

4

Theory

CH20 - NITROGEN COMPOUNDS

(a) Identify compound U which contains only three elements............................................................ [1](b) Describe the reagents an...

2024 Winter

2

Theory

CH20 - NITROGEN COMPOUNDS

(a) An aqueous solution of phenol, $C_6H_5OH$, is acidic at 298K.Explain why phenol is more acidic than water............................................

2024 Winter

2

Theory

CH20 - NITROGEN COMPOUNDS

Amino acids are molecules that contain —NH₂ and —COOH functional groups.Glycine, $H_2NCH_2COOH$, is the simplest stable amino acid.(a) The isoel...

2024 Spring

2

Theory

CH20 - NITROGEN COMPOUNDS

(a) State the relative basicities of phenylamine, $\text{C}_6\text{H}_5\text{NH}_2$, benzylamine, $\text{C}_6\text{H}_5\text{CH}_2\text{NH}_2$, and am...

2024 Summer

1

Theory

CH20 - NITROGEN COMPOUNDS

(a) Isomer P and isomer Q have identical physical and chemical properties, with the exception of two specific properties. One of these two properties ...

2024 Winter

3

Theory

CH20 - NITROGEN COMPOUNDS

A reaction scheme is shown in Fig. 7.1.The reagents needed for reaction 2 and reaction 3 are stated.Reaction 5 takes place when $C_2H_5NH_2$ is mixed ...

2024 Winter

1

Theory

CH2 - ATOMIC STRUCTURE

(a) Complete the table to show the composition and identity of some atoms and ions.[Table]name of element | nucleon number | atomic number | number of...

2016 Summer

1

Theory

CH4 - STATES OF MATTER

D, E, F, and G are four consecutive elements in the fourth period of the Periodic Table. (The letters are not the actual symbols of the elements.)D is...

2016 Summer

1

Theory

CH10 - GROUP 2

The elements in Group 2, and their compounds, show many similarities and trends in their properties.(a) Magnesium, calcium, strontium and barium all r...

2016 Summer

1

Theory

CH14 - AN INTRODUCTION TO ORGANIC CHEMISTRY

This question is about molecules with molecular formula $C_4H_8$.(a) Give the structures of a pair of **positional** isomers with the formula $C_4H_8$...

2016 Summer

1

Theory

CH22 - ANALYTICAL TECHNIQUES

(a) Complete the diagram to show the mechanism of reaction 1. Include all necessary charges, partial charges, lone pairs and curly arrows.H3C—C—Br...

2016 Summer

Theory

CH2 - ATOMIC STRUCTURE

(a) Complete the table to show the composition and identity of some atoms and ions.[Table_1]name of element | nucleon number | atomic number | number ...

2016 Summer

2

Theory

CH5 - CHEMICAL ENERGETICS

The elements in Group 17, the halogens, and their compounds, show many similarities and trends in their properties. Some data are given for the elemen...

2016 Summer

3

Theory

CH6 - ELECTROCHEMISTRY

Acidified potassium dichromate(VI) can oxidise ethanedioic acid, $H_2C_2O_4$. The relevant half-equations are shown. $$Cr_2O_7^{2-} + 14H^+ + 6e^- \r...

2016 Summer

2

Theory

CH22 - ANALYTICAL TECHNIQUES

This question is about molecules with molecular formula $C_4H_8O_2$.(a) Give the structural formulae of the pair of extbf{chain} isomers with the for...

2016 Summer

2

Theory

CH17 - HYDROXY COMPOUNDS

A reaction sequence based on propan-1-ol is shown. (a) Reactions 1 and 2 can both be carried out using the same reagents. (i) Identify suitable rea...

2016 Summer

2