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

MCQ

CH1 - ATOMS, MOLECULES & STOICHIOMETRY

This question refers to isolated gaseous atoms.In which atom are all electrons paired?

2018 Summer

1

MCQ

CH3 - CHEMICAL BONDING

Which compound has a boiling point that is influenced by hydrogen bonding?

2018 Summer

MCQ

CH14 - AN INTRODUCTION TO ORGANIC CHEMISTRY

Which fuel would produce the largest mass of CO$_2$ when 10 kg of the fuel undergo complete combustion?

2018 Summer

MCQ

CH5 - CHEMICAL ENERGETICS

The diagram shows the Boltzmann distribution of energies in a gas. The gas can take part in a reaction with an activation energy, $E_a$. The gas is ma...

2018 Summer

MCQ

CH14 - AN INTRODUCTION TO ORGANIC CHEMISTRY

Which molecule has no overall dipole?

2018 Summer

1

MCQ

CH3 - CHEMICAL BONDING

Which solid contains more than one type of bonding?

2018 Summer

1

MCQ

CH5 - CHEMICAL ENERGETICS

Enthalpy changes of combustion can be used to determine enthalpy changes of formation. The following equation represents the enthalpy change of format...

2018 Summer

MCQ

CH6 - ELECTROCHEMISTRY

Ethanedioate ions, $\text{C}_2\text{O}_4^{2-}$, react with a suitable reagent to form $\text{CO}_2$. A half-equation for this reaction is shown. $\te...

2018 Summer

MCQ

CH6 - ELECTROCHEMISTRY

Oxidation numbers should be used to answer this question.A redox reaction takes place between hydroxylammonium ions, $[\text{NH}_3\text{OH}]^+$, and a...

2018 Summer

MCQ

CH5 - CHEMICAL ENERGETICS

Element X has a higher first ionisation energy than element Y.Two students state what they believe is one factor that helps to explain this.student 1 ...

2018 Summer

1