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What is the source of sulfur dioxide, and the harmful effects of sulfur dioxide?

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The source of sulfur dioxide comes from burning of fossil fuels, and volcanic activity.

Sulfur dioxide can dissolve in rain water high up in the atmosphere, forming acid rain.

Acid rain speeds up the corrosion of buildings and structures made of limestone or reactive metals, like steel.

Acid rain makes water too acidic, which can be harmful to aquatic organisms.

Acid rain removes essential metal ions needed by plants, such as calcium, potassium, magnesium ions from the soil, affecting the health of plants.

List the 3 consequences of global warming.

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Melting of ice in the polar ice caps, mountain glaciers, resulting in the rise in sea level, resulting in flooding of low lying regions.

Increase in average global temperatures

Climate change, resulting in an increase in extreme weather conditions, like heat waves and droughts

What is the importance of the ozone layer?

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The ozone layer filters out some of the harmful UV radiation from the sun, reducing the amount of harmful UV rays reaching the Earth’s surface.

The harmful UV radiation can cause skin cancer, genetic mutations, eye damage, and is harmful to marine life.

List down the metals reactivity series, from most reactive metal to the least reactive metal.

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Potassium, (most reactive)
Sodium,
Calcium,
Magnesium,
Aluminium,
(Carbon),
Zinc,
Iron,
Tin,
Lead,
(Hydrogen),
Copper,
Silver,
Gold,
Platinium (least reactive)

Use this mnemonic to help u remember.
” Please Stop Calling Me A Cute Zebra In The Lion Hunting Class Sensitive Giant Panda.”

What is Brownian Motion? What causes Brownian Motion?

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Brownian motion refers to the constant, random motion of small suspended particles in a fluid.

Brownian motion is caused by the constant, random bombardment of the fluid particles on the small suspended particles from all directions, causing the small suspended particles to move constantly in a haphazard motion.

A dust particle suspended in air moving in constant, random motion is an example of Brownian motion.

Describe how a barometer work.

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A barometer consist of a long glass tube and a liquid reservoir, usually mecury.

The tube is first submerged in the reservoir, and completely filled with the liquid in the reservoir.

Then, the tube is held inverted to a vertical position, with the mouth of the tube still in the liquid reservoir, and a pocket of vacuum above the liquid column inside the tube.

The atmospheric pressure exerts a force on the surface of the liquid reservoir, pushing the liquid up the tube. The pressure of the liquid column in the tube will be equal to the atmospheric pressure.

Describe how a hydraulic press work.

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A hydraulic press consists of two pistons of different sizes.

The space between the two pistons is filled completely with a liquid, usually hydraulic oil.

When a force is applied on the smaller piston, the pressure exerted on the liquid at the smaller piston is transmitted equally throughout the liquid.

Hence, the same pressure is also exerted at the bigger piston.

Since P = F/A, the F/A ratio will be the same at both pistons.

Since A1 < A2, hence F1 < F2.

So a smaller effort on the smaller piston (F1) will be able to lift a bigger load at the bigger piston (F2).

Describe a simple test for the presence of a reducing agent using aqueous potassium manganate (VII) solution.

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Add a few drops of acidified potassium manganate(VII) solution to a solution containing an unknown agent.

If a reducing agent is present in the solution, the KMnO4 solution will turn from purple to colorless.

In the presence of a reducing agent, a redox reaction occurs, turning the Mn7+ ion in KMnO4 (which is purple) to Mn2+ ion (which is colorless or slightly pinkish).