chapter 8 alloy

8/8/2019 Chapter 8 Alloy

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Chapter 8Chapter 8

Chemicals in industryChemicals in industry


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8.1 Allyos8.1 Allyos

1. Alloys --- alloy is formed when some

__________________ or

_________________ is added intoanother pure metal in ______________

condition

2. Process ________________

Pure metal

Non-metal

Molten

Alloying


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3. In pure metals, atoms are arranged

_______________ and orderlyclosely


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4. When foreign atoms are added into the

pure metal, the layers of atom of the pure

metal will be stopped from sliding over

each other.

5. The pure metal which is soft and weak

before alloying becomes ______________and ________________

StrongHarder


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Formation of alloys changes theFormation of alloys changes the

properties of metalsproperties of metals

1. Purpose of producing alloy:

(a) _________________________

- to make metal look more attractive like pewter

(b) ________________________

- Alloys are harder- suitable to make things

(c) _________________________

- stainless steel, an alloy will not corrode and

rust

Improve appearance

Harden metals

Prevent corrosion


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Superconductor alloySuperconductor alloy


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1. Superconductor alloy able to conduct_________ without resistance which occurs at

very low temperature2. The flow of current with zero resistance is called

___________________

3. Superconductivity occurs at very low

temperature- the alloys are cooled in liquidnitrogen or helium. Example: Niobium-germanium operates at -250C

4. This alloys are very strong magnets with

magnetic strength million times more than anordinary magnets.

5. Problem: _________________________especially in cooling down the superconductor.

Current

Superconductivity

High maintenance cost


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6.6.Uses of superconductor alloys:Uses of superconductor alloys:


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8.2 The production anduses of8.2 The production anduses of

ammoniaammonia


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1. Ammonia is produced industrially through

___________________

2. ________________ gas is produced from

fractional distillation of liquid air while

_______________ gas is produced from the

reaction of steam with natural gas.3. ________________ and

________________ are mixed compressed,

then passed through an iron catalyst to form________________

Haber process

Nitrogen

hydrogen

Nitrogen

hydrogen

ammonia


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Uses of ammoniaUses of ammonia


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8.3 The effects of industrial waste disposal8.3 The effects of industrial waste disposal

1. ______________________________________

(a) Example: fossil fuels include petroleum, naturalgas and coal

(b) Burning of these fuels will produce wastes likesulphur dioxide, nitrogen dioxide,

____________________, _________________,soot, ___________ and _________

(c) Effects on environment:

- _____________________

- _____________________- photosynthesis disturb

- respiratory damage

- _____________________

Burning of fossil fuels

Carbon dioxideC

arbon monoxideDust Smoke

Acid rain

Greenhouse effect

Thinning of ozone layer


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2. _________________________________________

(a) Many chemical industry- produce lot of chemical

wastes like __________, ___________, nitratecompounds, phosphate, lead, ______________,

nickel, arsenic and cadmium.

(b) incorrect disposal would cause problems like:

- cancer

- ________________ - from polluted water

- reduction in the number of

_____________________ and ________- low levelof oxygen dissolved in water

- photosynthesis process is disrupted

Toxic waste from chemical industry

acids alkalimercury

Skin diseases

Aquatic animals Plants


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3. ___________________________________

(a) Usage of chemical fertilizers, pesticides,insecticides, herbicides and fungicides cause

____________ and ___________ pollution

(b) These substances promote the growth of

____________ in the water which blocks

sunlight from reaching the aquatic plants in

the river or pond, causing them to die

Agricultural waste

soil water

algae


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4._______________________________(a) cause _____________,

_____________, disability and death

Radioactive waste

cancer

infertility


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8.5 Preservation and conservation of the8.5 Preservation and conservation of the

environmentenvironment

1.Preservation:

-active maintenance taken in order to ensureliving things and the environment ismaintained in their original and balancedstate

2.Conservation:

- management of plant and animal speciesto protect the habitats they live in whileusing all the available resources fordevelopment


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3. Steps:

(a) _________________________

- legal action will be take on factories

operators who pollute the environment

(b) _________________________

- many ways to dispose and control

industrial waste through modern

technology.

- example:

Law enforcement

Use of technology


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Example :


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(c) _______________________________

- environmental sciences curriculum,____________________ and

_______________ can be taken in

schools and to the public to inform themproper ways to control ant prevent

pollution

Education

campaigns

Seminars

chapter 8 alloy

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