null
US
Entrar
Registre-se gratuitamente
Registre-se
Detectamos que o JavaScript não está habilitado no teu navegador. Habilite o Javascript para o funcionamento correto do nosso site. Por favor, leia os
Termos e Condições
para mais informações.
Próximo
Copiar e Editar
Você deve estar logado para concluir esta ação!
Inscreva-se gratuitamente
2423920
B6d Summary
Descrição
B6d summary
Sem etiquetas
biology
ocr gateway
b6
biofuels
biomass
biogas
biology
b6
cambridge igcse/ gcse
Mapa Mental por
Ciara Comerford
, atualizado more than 1 year ago
Mais
Menos
Criado por
Ciara Comerford
aproximadamente 9 anos atrás
11
1
0
Resumo de Recurso
B6d Summary
What are biofuels?
produced by burning biomass
e.g. wood, alcohol, biogas
BIOMASS
photosynthesis produces biomass in plants
cardon dioxide + water --> glucose + oxygen
how is energy transferred?
fast growing trees can be burnt
releasing heat
biomass can be fermented by yeast & bacteria
to create products e.g. biogas
can be used as fuels
BIOGAS
Contains...
70% methane (CH4)
30% carbon dioxide (CO2)
also contains traces of...
hydrogen
nitrogen
hydrogen sulfide
biogas containing >50% methane burns easily
but around 10% methane is eplosive
displaces air & reduces O2 levels
restricting respiration
so keep well ventilated
higher risk of explosion
if there are explosions landfill sites
may be unusable for many years
production is fastest at 32-35°C
because fermenting bacteria grow best at this temp.
Gasohol
mixture of ethanol (10%) and petrol (90%)
most economically viable in places
where there is plenty of sugar cane & not a lot of oil
ethanol produced by fermentation of glucose by yeast
sugar cane works as a source of glucose
Advantages
RENEWABLE
crops which are decomposed to make biogas
quickly replaced with new plants
CARBON NEUTRAL
plants grown to make biogas photosynthesise
removing CO2 from the atmosphere
balancing out the release of CO2
from burning the biofuel
but the biofuel has to be burnt at the same rate
as new biomass is produced
of biogas
reduces fossil fuel consumption
produces no particulates when burnt
no overall increase in levels
of greenhouse gases
Disadvantages
of biogas
doesn't contain as much energy
as same volume of natural gas
because it is more dilute
natural gas has as much higher % of CH4
can lead to habitat loss
and so extinction of species
large areas of land sometimes cleared of vegetation
to create space to produce biofuels
causes extinction of species due to habitat loss
and change in food availability
Quer criar seus próprios
Mapas Mentais
gratuitos
com a GoConqr?
Saiba mais
.
Semelhante
Biology AQA 3.1.3 Cells
evie.daines
Biology AQA 3.2.5 Mitosis
evie.daines
Biology AQA 3.1.3 Osmosis and Diffusion
evie.daines
Biology- Genes, Chromosomes and DNA
Laura Perry
Biology- Genes and Variation
Laura Perry
Enzymes and Respiration
I Turner
GCSE AQA Biology - Unit 2
James Jolliffe
GCSE AQA Biology 1 Quiz
Lilac Potato
Using GoConqr to study science
Sarah Egan
Cells and the Immune System
Eleanor H
GCSE Biology AQA
isabellabeaumont
Explore a Biblioteca