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 how the molecules in the exhaust gases diffuse into the air.Which statement describes what happens to these molecules next?A. The mo...

2009 Summer

Theory

CH2 - SEPARATING SUBSTANCES

A student takes 2 g samples of calcium carbonate and adds them to 20 cm$^3$ samples of dilute hydrochloric acid at different temperatures. She measure...

2009 Summer

Theory

CH2 - SEPARATING SUBSTANCES

The diagram shows the paper chromatograms of four substances, W, X, Y and Z. Which two substances are pure?A W and X B W and Y C X and Y D X and Z

2009 Summer

Theory

CH3 - ATOMS AND ELEMENTS

An element S has the proton number 18. The next element in the Periodic Table is an element T. Which statement is correct?A Element T has one more ele...

2009 Summer

Theory

CH3 - ATOMS AND ELEMENTS

Which numbers are added together to give the nucleon number of an ion?A number of electrons + number of neutronsB number of electrons + number of prot...

2009 Summer

Theory

CH3 - ATOMS AND ELEMENTS

The electronic configuration of an ion is 2.8.8.What could this ion be?[Table_1]

2009 Summer

Theory

CH4 - ATOMS COMBINING

The diagrams show the structures of two forms, P and Q, of a solid element. What are suitable uses of P and Q, based on their structures?[Table_1]

2009 Summer

Theory

CH4 - ATOMS COMBINING

Element V forms an acidic, covalent oxide. Which row in the table shows how many electrons there could be in the outer shell of an atom of V? [Table...

2009 Summer

Theory

CH4 - ATOMS COMBINING

When sodium chloride is formed from its elements, each chlorine atom ......1...... one ......2....... Which words correctly complete gaps 1 and 2? [...

2009 Summer

Theory

CH5 - REACTING MASSES AND CHEMICAL EQUATIONS

Nitrogen and hydrogen react together to form ammonia.$N_2 + 3H_2 \rightarrow 2NH_3$When completely converted, 7 tonnes of nitrogen gives 8.5 tonnes of...

2009 Summer