Final M.3 second semester

Two types of polymer are shown below. Which of the following statements concerning these polymers is correct?

X is thermosetting whereas Y is thermoplastic

Both are thermoplastic

X is thermoplastic whereas Y is thermosetting

Both are thermosetting

The difference between traditional ceramics and new ceramics is that most traditional ceramics are based primarily on silicates whereas the most new ceramics are based on oxides, carbides, or nitrides: this state true or false

True

False

Which of the following contains significant amounts of aluminum oxide

Alumina

Quartz or silica

Glass products are based primarily on which one of the following minerals

Alumina

Silica

Which one of the three polymer types is not a plastic

Elastomers

Thermoplastics

Thermosets

He defining property of a thermoplastic polymer is that it can be heated from a solid state to a viscous liquid state and then cooled back down to solid, and that this heating and cooling cycle can be applied multiple times

True

False

Which one of the following is the chemical formula for the repeating unit in polyethylene

CH2

C2H4

C3H6

C5H8

Which of the following polymers are normally thermoplastic

Bekalite

Polyethylene

Vulcanization in car tire

Compared to thermoplastics, thermosetting polymers are characterized by which of the following properties

Cannot be remelted

Capable of higher service temperatures

Less ductile

All of them

A chemical reaction is a process in which

Products change into reactants

Substances change state

Amount of atoms reactants and products are equal (the law of conservation of mass)

During a chemical reaction,

New elements are produced

Atoms are destroyed

Atoms are rearranged

Elements are destroyed

An equation is balanced by

Adding coefficients

Changing subscripts no.

Adding elements as necessary

Erasing elements as necessary

What are the reactants in the following chemical equation: Zn + CuSO4 -----> ZnSO4 + Cu

Zinc and copper

Zinc and copper (II) sulfate

Zinc sulfate and copper

Only zinc

The polysaccharide or carbohydrates as the natural polymer scattering the tiny formation molecule are water H2O, what this type of polymerisation reaction?

Addition

Condensation

In the chemical reaction CH4 + 2O2 → CO2 + 2H2O, there are reactants on the left of the equation and products on the right. If you count the atoms in the reactants, there are

4 carbon atoms, 4 hydrogen atoms, and 2 oxygen atoms

1 carbon atom, 4 hydrogen atoms, and 2 oxygen atoms

1 carbon atom, 4 hydrogen atoms, and 4 oxygen atoms

4 carbon atoms, 4 hydrogen atoms, and 4 oxygen atoms

If the reactants on the left side of a chemical equation are C3H8 + 5O2, the products in a balanced equation could be

4CO2 + 3H2O

3CO2 + 4H2O

2CO2 + 3H2O

3CO + 4H2O

If two substances react and the temperature of the mixture increases, the reaction is

Endothermic

Exothermic

If two substances react and the temperature of the mixture decreases, the reaction is

Endothermic

Exothermic

This following reaction is the same as which set? Na + H2O-----> NaOH+H2

This following reaction is the same as which set? PbI+ KNO3----->PbNO3+KI

CH3COOH + NaHCO3 +E ----> CH3COONa + CO2+ H2O is______?

Endothermic

Exothermic

When put steel wool in vinegar(acetic acid) this reaction energy type is______?

Endothermic

Exothermic

What are the missing coefficients for the equation ? Al2 (SO4)3(aq) + KOH(aq) ---> Al(OH)3(aq) + K2SO4(aq)

1,3,2,3

2,12,4,6

4,6,2,3

1,6,2,3

If you rewrite the following word equation as a balanced chemical equation, what will the coefficient and symbol for fluorine be? Nitrogen trifluoride or NF3-----> nitrogen + fluorine

6F2

3F2

Thermosetting materials are___?

The plastics which can be softened even after they have set and hardened

The plastics which require heat and pressure to mould them into shape

None of them correct

Final M.3 second semester

More Quizzes