Theory

CH18 - POLYMERS

Lactic acid can be made from corn starch. It polymerises to form the polymer, polylactic acid (PLA) which is biodegradable. (a) Suggest two advant...

2009 Summer

Theory

CH18 - POLYMERS

A macromolecule is a very large molecule. Macromolecules can be made by joining smaller molecules together. This is called polymerisation. Which row i...

2010 Summer

Theory

CH18 - POLYMERS

A macromolecule is a very large molecule.Macromolecules can be made by joining smaller molecules together. This is called polymerisation.Which row in ...

2010 Summer

Theory

CH18 - POLYMERS

A macromolecule is a very large molecule.Macromolecules can be made by joining smaller molecules together. This is called polymerisation.Which row in ...

2010 Summer

Theory

CH18 - POLYMERS

Hydrolysis is used in chemistry to break down complex molecules into simpler ones.(a) Compounds containing the group $\overset{O}{\parallel}C$ or $\te...

2010 Summer

Theory

CH18 - POLYMERS

The hydrolysis of complex carbohydrates to simple sugars is catalysed by enzymes called carbohydrases and also by dilute acids.(a) (i) They are both c...

2010 Summer

Theory

CH18 - POLYMERS

The hydrolysis of complex carbohydrates to simple sugars is catalysed by enzymes called carbohydrases and also by dilute acids.(a) (i) They are both c...

2010 Summer

Theory

CH18 - POLYMERS

Monomers polymerise to form polymers or macromolecules.(a) (i) Explain the term polymerise...............................................................

2010 Winter

Theory

CH18 - POLYMERS

In the absence of oxygen, certain bacteria decompose carbohydrates to biogas. This is a mixture of gases mainly methane and carbon dioxide. Biogas is ...

2010 Winter

Theory

CH18 - POLYMERS

Synthetic polymers are widely used in the modern world.(a) Their use has brought considerable advantages to modern life as well as some disadvantages....

2010 Winter

Theory

CH1 - STATES OF MATTER

The diagram shows a cup of tea. Which row describes the water particles in the air above the cup compared with the water particles in the cup?[Table_1...

2010 Summer

Theory

CH2 - SEPARATING SUBSTANCES

A fruit drink coloured orange contains a dissolved mixture of red and yellow colouring agents. One of these colouring agents is suspected of being ill...

2010 Summer

Theory

CH1 - STATES OF MATTER

A student carries out an experiment to find how fast 3 cm pieces of magnesium ribbon dissolve in 10 cm³ samples of sulfuric acid at different tempera...

2010 Summer

Theory

CH4 - ATOMS COMBINING

Which row shows the change that takes place when element X gains the new particle shown?[Table_1]Table 1| | particle gained | change || --- ...

2010 Summer

Theory

CH3 - ATOMS AND ELEMENTS

The diagram shows an atom.key𝑒 electronnucleus containing nine particlesWhat is the proton number and neutron number of the atom?[Table_1]| | ...

2010 Summer

Theory

CH3 - ATOMS AND ELEMENTS

The symbols of two atoms may be written as shown.$$^{52}_{23}\text{X} \quad {}^{52}_{24}\text{Y}$$Which statement about these atoms is correct?A. They...

2010 Summer

Theory

CH14 - MAKING USE OF METALS

Which name is given to mixtures of metals?A. alloysB. compoundsC. oresD. salts

2010 Summer

Theory

CH4 - ATOMS COMBINING

Element X has six electrons in its outer shell.How could the element react?A by gaining two electrons to form a positive ionB by losing six electrons ...

2010 Summer

Theory

CH4 - ATOMS COMBINING

In which compounds are pairs of electrons shared between atoms?1. sodium chloride2. methane3. lead bromideA 1 only B 2 only C 1 and 3 D 1, 2 and 3

2010 Summer

Theory

CH5 - REACTING MASSES AND CHEMICAL EQUATIONS

Hydrogen and chlorine react as shown.What is the equation for this reaction?A. $2H + 2Cl \rightarrow 2HCl$B. $2H + 2Cl \rightarrow H_2Cl_2$C. $H_2 + C...

2010 Summer