Kuiz Sains Tambahan Tingkatan 5 Bab 4 Set 1

SELAMAT DATANG Kuiz Sains Tambahan Tingkatan 5 Bab 4 Set 1

Tenaga Dan Perubahan Kimia (English)

KUIZ INI MENGANDUNGI 10 SOALAN

What is the specific process that uses light energy to split water molecules into hydrogen ions and oxygen during photosynthesis?

Electrolysis

Hydrolysis

Photosynthesis

Photolysis

None

What happens to the electrons at the positive terminal (cathode) of a simple chemical cell, such as one made of zinc and copper?

They are released by the copper electrode into the solution.

They are accepted by positive ions from the electrolyte.

They flow from the cathode to the anode through the external wire.

They combine with the atoms of the cathode material.

None

During the electrolysis of a dilute aqueous sodium chloride (NaCl) solution using inert electrodes, what gas is produced at the anode?

Oxygen

Hydrogen

Sodium

Chlorine

None

Which energy transformation occurs in an electrolytic cell?

Heat energy to electrical energy

Chemical energy to electrical energy

Electrical energy to chemical energy

Light energy to chemical energy

None

In a photochromic lens, what causes the glass to darken upon exposure to sunlight?

Silver halide crystals decompose into dark silver particles.

A heat-sensitive dye embedded in the glass changes color

The glass absorbs light and then releases it as heat.

The glass undergoes a permanent chemical change

None

Why are photosensitive chemicals such as silver bromide and hydrogen peroxide typically stored in dark or opaque bottles?

To keep the chemicals at a constant cool temperature.

To prevent chemical reactions with the glass container.

To protect them from decomposition caused by light.

To prevent them from evaporating quickly.

None

Which of the following reaction equations represents an endothermic process?

C+2S→CS 2 ΔH=+320 kJ mol−1

2Mg + O2 →2MgO ΔH = −1204 kJ mol−1

Zn+2HCl→ZnCl2 +H2 ΔH = −152 kJ mol−1

C2H5OH + 3O2 →2CO2 + 3H2O ΔH = −1270 kJ mol−1

None

What is the primary function of adding cryolite (Na3AlF6) to aluminium oxide (Al2O3) during the industrial extraction of aluminium?

To act as a catalyst and speed up the reaction.

To prevent the carbon anodes from oxidizing.

To increase the purity of the final aluminium product.

To significantly lower the melting point of aluminium oxide.

None

In the industrial process of purifying copper, what is the role of the impure copper block?

It is used to stir the electrolyte solution.

It functions as the electrolyte for the cell

It serves as the cathode, where pure copper is deposited.

It acts as the anode, which dissolves during electrolysis

None

10.

In a simple chemical cell constructed with magnesium and copper electrodes in an electrolyte, why does the magnesium strip become thinner over time?

Magnesium atoms lose electrons to become magnesium ions.

Copper ions from the solution deposit onto the magnesium strip.

The magnesium strip physically flakes off due to the electric current.

Electrons from the copper strip react with the magnesium.

None

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