Chemistry and Biology and Physics

9I chemistry and biology set

what is a chemical reaction?

A change in which one or more new substances are formed

what is an explosion?

A rapid expansion in volume, releasing a lot of energy and gas

define flammable

A substance that catches fire easily

what is an implosion?

An object is destroyed by collapsing in on itself

what is the particle theory?

A theory used to explain the different properties and observations of solids, liquids and gases

what is a physical change?

A change in which no new substances are formed

whats an example of a physical change?

change in state

what is pressure?

The amount of force pushing on a certain area.

where are the reactants in word equation?

on the left

where are the products in word equation?

on the right

what is a native state of a metal?

When a metal is found in the Earth as an element

what is oxidation?

Reaction in which a substance gains oxygen

what is the reactivity series?

A list of metals that shows them in order of reactivity with the most reactive metal at the top

what is rust?

a crumbly solid formed when iron corrodes

what is a sacrificial protection/agent?

Using a more reactive metal to protect another metal from reacting

what is endothermic?

A reaction in which energy is transferred to the reactants from the surroundings.

what is exothermic?

A reaction in which energy is transferred from the reactants to the surroundings.

does the temperature of an exothermic reaction increase or decrease its surroundings?

increase

does the temperature of an endothermic reaction increase or decrease its surroundings?

decrease

what is a hydrocarbon?

A compound containing hydrogen and carbon only

what is an oxidising agent?

A substance that provides oxygen to oxidise another substance

what is displacement?

When one element takes the place of another element in a compound that is less reactive

what is electrolysis?

Breaking down a substance using electricity

what is a mineral?

An element or compound forming distinct grains in rocks

what is a ore?

A rock that contains enough of a certain mineral to make it worth mining

what is a reductive reaction?

a reaction in which oxygen is removed from a substance

what is a reducing agent?

A substance that removes oxygen from another substance

What type of change doesn’t make a new substance, is easily reversible and is mainly a change in state or mixed together

a physical change

what are examples of physical changes?

boiling, freezing, condensing and freezing

what type of reaction always makes one or more new substances, is difficult to reverse and have different properties to the original properties?

a chemical reaction

what are examples of chemical changes?

combustion, neutralisation, thermal decomposition

what is gas pressure?

the force of gas hitting a container

what does increasing the temperature, increasing the number of particles in the container and decreasing the volume of the container do?

changes gas pressure

What is the acronym for the reactivity series?

Pink salmon can make a couple zebras in legoland have countless silver-purple gibbons

what is smelting?

the extraction of metal by heating and melting

what’s the process of electrolysis after the substance has been melted

the molten metal goes to the negative anode in water and the non metal goes to the positive anode

Which tissue transports sugar around a plant?

phloem tissue

What name is given to the chemicals that are added to plants in order to provide them with essential chemical elements?

fertilisers

Which type of tissue is found covering the organs of plants?

epidermal tissue

Why is glucose unsuitable for storage in plants?

it is soluble

In order to make proteins, plant cells need nitrogen. They absorb nitrogen in the form of __________ ions from the soil. What one word completes the sentence?

nitrate

Nitrogen is a gas and cannot be added to soil. What type of chemical should be added to the soil to cure the unhealthy plant? (You have to be more specific than 'fertiliser'.)

nitrate ions

what are signs of nitrogen deficiencies?

stunted growth and yellow leaves

The movement of water from the roots, through the plant and out of the leaves is known as the... what?

transpiration

what surrounds the stomata?

the guard cell

Most photosynthesis occurs in the …., which is just below the upper epidermis in a leaf. Which phrase completes this sentence?

Palisade layer

In a plant, when the rate of respiration is less than the rate of photosynthesis, what happens to the volume of carbon dioxide that is released?

it decreases

Plants use carbon from carbon dioxide to make carbohydrates, fats and oils. What else do they make from carbon? (2 words)

Proteins or amino acids

In photosynthesis, plants combine … with …, a gas present in the atmosphere, to make a sugar.

water and carbon dioxide

The rate of photosynthesis is controlled by light intensity, availability of carbon dioxide and which other factor?

water

What name is given to a factor which is preventing any increase in photosynthesis?

limiting factor

What other factor (apart from light intensity) would increase as the light is moved nearer in a pondweed experiment?

temperature

Plants store carbohydrates as starch. Name one other substance used for food storage in plants, especially in their seeds.

fats/oils/lipids

Apart from plants, what other group of organisms photosynthesises?

algae and protists

In what form do plant cells store carbohydrates?

starch

Name the type of plankton that is able to carry out photosynthesis.

phytoplankton

In order to make proteins from glucose, what other substance do plant cells need?

nitrates

what is marine snow?

dead organisms and waste that sink from the surface of the sea

The nitrogen in fertilisers is used by crop plants to make __________ (one word), which means that they can give a greater yield. What is the missing word?

proteins

what deficiency is the reason for yellow leaves

magnesium deficiency

When plants respire, what gas is released into the atmosphere?

carbon dioxide

Other than oxygen, the level of what substance needs to be maintained to give cells a constant supply of energy?

glucose

Which chemical, apart from glucose, is used in aerobic respiration?

oxygen

What name is given to animals such as earthworms that feed on dead and decaying material?

detritivores

What does the upper epidermis do?

Allows light to get through

how is more palisade mesophyll stored due it's upright arrangement and what does it store?

Maximises the surface area of chloroplasts

Why is the spongy mesophyll specially arranged with lots of air space?

To maximise efficient gas exchange

where does the water flow up to the leaf?

the xylem vessels

what are xylem vessels made up of?

hollow cells

what is the secondary reason water is needed in a leaf?

mineral salts are dissolved in it

what do nitrates make (one word)

?

proteins

what does water in the plant stop?

wilting

where do gases diffuse in the leaf cell?

the stomata

why are leaves thin?

so gas exchange isn’t difficult

what’s the word equation for aerobic respiration? (use -> for the arrow and it will become an arrow)

glucose + oxygen → carbon dioxide + water

what are 3 reasons a plant needs glucose?

release of energy, making new energy stores and for cell growth.

where are new substances made by plants carried around?

the phloem vessel

what is a negative of clearing land?

destroys habitats and lack of roots causes soil erosion

what is a negative of using Pesticides, herbicides and insecticides (2 reasons)?

It kills useful organisms and damages the food web

what is the specific name for the over-fertilisation of a river, making the nutrient rich water overfeed and eventually kill all organisms in a river?

eutrophication

what is the name for famers selecting an organism with specific characteristics, then breeding the best offspring until the best characteristics are found only in the organism?

selective breeding

what is the name of the process where farmers might try and breed two organisms with different characteristics, hoping to get offspring with both varieties?

cross-breeding

what is the charge of a nucleus?

positive

what happens when you rub two materials together?

electrons may be transferred

what is the name of the the space around a charged object?

electric field

what is resistance?

how easy or difficult it is for an electric current to flow through it

the higher the voltage….

the higher the current

the higher the resistance….

the lower the current

what are factors that affect the conductivity of a metal?

the material, the length and the thickness

what is the unit for measuring resistance?

ohms

what is the formula for voltage?

current x resistance

what is a bar magnet?

a permanent magnet

what is an electromagnet?

a coil of wire with an electric current flowing through it

how can you make an electromagnet stronger?

increasing the number of coils, increasing the voltage and putting a metal rod through it.

what is it called when a wire is carrying a current and crosses a magnetic field, causing the wire to experience a force?

motor effect