Theory

CH5 - CHEMICAL ENERGETICS

Separate samples of $Na_2CO_3$ and $NaHCO_3$ react with $HCl(aq)$ to produce the same products, as shown in Table 2.1.[Table_1](a) Complete the reacti...

2024 Summer

2

Theory

CH5 - CHEMICAL ENERGETICS

(a) Write an equation to show the reaction for the standard enthalpy change of formation of $\text{H}_2\text{O}$. Include state symbols..................

2024 Summer

3

Theory

CH5 - CHEMICAL ENERGETICS

(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

CH5 - CHEMICAL ENERGETICS

(a) Define enthalpy change of formation..................................................................................................................

2024 Summer

4

Theory

CH5 - CHEMICAL ENERGETICS

(a) Predict and explain the variation in enthalpy change of hydration for the ions F^−, Cl^−, Br^− and I^−. .....................................

2024 Winter

2

Theory

CH5 - CHEMICAL ENERGETICS

Potassium iodide, KI, is used as a reagent in both inorganic and organic chemistry.(a) KI forms an ionic lattice that is soluble in water.(i) Define e...

2024 Spring

4

Theory

CH5 - CHEMICAL ENERGETICS

(a) Describe the trend in the solubility of the sulfates of magnesium, calcium and strontium. Explain your answer........................................

2024 Summer

3

Theory

CH5 - CHEMICAL ENERGETICS

(a) Equation 1 shows water acting as a Brønsted–Lowry acid. equation 1 \[ \text{H}_2\text{O} + \text{NO}_2^- \rightleftharpoons \text{HNO}_2 + \tex...

2024 Spring

2

Theory

CH5 - CHEMICAL ENERGETICS

(a) Carbon disulfide, $\text{CS}_2$, is flammable and reacts readily with oxygen, as shown in reaction 1.reaction 1 $\text{CS}_2(g) + 3\text{O}_2(g) \...

2024 Summer

2

Theory

CH5 - CHEMICAL ENERGETICS

(a) Define standard electrode potential, $E^\text{o}$, including a description of standard conditions.(b) (i) An electrochemical cell is set up to mea...

2024 Summer

3

Theory

CH1 - ATOMS, MOLECULES & STOICHIOMETRY

Some intercontinental jet airliners use kerosene as fuel. The formula of kerosene may be taken as $C_{14}H_{30}$.(a) To which homologous series of com...

2011 Summer

6

Theory

CH15 - HYDROCARBONS

(a) (i) What is meant by the term `cracking` and why is it carried out?..................................................................................

2011 Summer

4

Theory

CH10 - GROUP 2

(a) State the formula of each of the calcium compounds U to Y.   U V W X Y (b) Compound Y may be converted into compound V. Out...

2011 Summer

2

Theory

CH18 - CARBONYL COMPOUNDS

Ketones are widely used as solvents and as intermediates in the chemical industry.Ketones contain the reactive keto group, $\text{C=O}$.(a) Propanone,...

2011 Summer

3

Theory

CH5 - CHEMICAL ENERGETICS

(a) When calcium carbide is reacted with water, ethyne and calcium hydroxide are formed. Construct a balanced equation for this reaction. (b) (i) Wh...

2011 Summer

2

Theory

CH7 - EQUILIBRIA

Ethanoic acid can be reacted with alcohols to form esters, an equilibrium mixture being formed.$$\text{CH}_3\text{CO}_2\text{H} + \text{ROH} \rightlef...

2011 Summer

3

Theory

CH16 - HALOGEN DERIVATIVES

(a) Use relevant bond energies from the Data Booklet, and the equation below to calculate a value for the bond energy of the C–F bond.CH$_2$ = CH$_2...

2011 Summer

3

Theory

CH10 - GROUP 2

(a) State the formula of each of the barium compounds R to W.R .................................... S ....................................T .............

2011 Summer

1

Theory

CH6 - ELECTROCHEMISTRY

(a) (i) Describe, with the aid of a fully labelled diagram, the industrial electrolysis of brine in a diaphragm cell. State what each electrode is mad...

2011 Summer

4

Theory

CH19 - CARBOXYLIC ACIDS AND DERIVATIVES

Although there are many different types of food eaten around the world, animal fats and/or vegetable oils are commonly used in cooking.Animal fats and...

2011 Summer

2