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

CH8 - REACTION KINETICS

The Boltzmann distribution for a gas at constant temperature is shown below. If the temperature of the gas is reduced by 10°C the graph changes shape...

2014 Summer

2

MCQ

CH2 - ATOMIC STRUCTURE

Which compound has the greatest total number of lone pairs of electrons in the valence shells of all of its atoms?

2014 Summer

2

MCQ

CH5 - CHEMICAL ENERGETICS

A reaction pathway diagram is shown. Which enthalpy change could the diagram not apply to?

2014 Summer

3

MCQ

CH2 - ATOMIC STRUCTURE

Use of the Data Booklet is relevant to this question.The most common ion-molecule reaction in gas clouds of the Universe is as shown.$$\text{H}_2(g) +...

2014 Summer

2

MCQ

CH6 - ELECTROCHEMISTRY

The electrolysis of brine using the diaphragm cell is an important industrial process. What happens at the anode?

2014 Summer

2

MCQ

CH5 - CHEMICAL ENERGETICS

Hydrazine, $\text{N}_2\text{H}_4$, is used as a rocket fuel because it reacts with oxygen as shown, producing 'environmentally friendly' gases.$\text{...

2014 Summer

2

MCQ

CH4 - STATES OF MATTER

A 10.0 cm^3 bubble of an ideal gas is formed on the sea bed where it is at a pressure of 2020 kPa. Just below the sea surface the pressure is 101 kPa ...

2014 Summer

2

MCQ

CH3 - CHEMICAL BONDING

Four substances have the physical properties shown in [Table_1].Which substance is an ionic solid?

2014 Summer

2

MCQ

CH5 - CHEMICAL ENERGETICS

The enthalpy change of formation of $\text{Mn(NO}_3)_2(\text{s})$ is $-696\text{ kJ mol}^{-1}$.The enthalpy change of formation of $\text{MnO}_2(\text...

2014 Summer

2

MCQ

CH3 - CHEMICAL BONDING

X is an element in Period 2. In which fluoride is the F−X−F angle the largest?

2014 Summer

2