Usually the beta particles are electrons with negative charge. And positrons are with positive charge. So they have the same mass and different charges. The answer is (3).
Deforestation, Desertification and Urbanization are very closely related phenomenon whose cause and effects are briefly discussed below.
<h3><u>Explanation:</u></h3>
Deforestation is caused due to cutting of trees for economic purposes and other poachers.
Deforestation effects the natural habitat of the animals of forests leading to endangering of different plants and animals. It also reduces diversity of environment, causes global warming, change in climate, rainfall patterns etc.
Desertification is caused due to deforestation, due to natural calamities like forest fires, overgrazing and even due to over population.
Desertification causes a huge loss to environment. Erosion of soil, deepening of ground water levels, loss of rainfall, draught are common. Rise in temperature and change of climates are also seen.
Urbanisation is caused by main two reasons - over population and rural to urban migration of people.
Urbanization has several good effects like growth of technologies etc. But it also increases disease rates due to increase in pollution. Several mental stress and depression are also seen to affect urban people more than rural ones.
The mass of Fe that is formed is 0.0532 grams
<u><em> Explanation</em></u>
Fe2O3 + 2 Al → Al2O3 + 2 Fe
Step 1: find the moles of Al
moles = mass/molar mass
from periodic table the molar mass of Al= 27 g/mol
moles = 0.0257g /27 g/mol =9.5 x10^-4 moles of Al
Step 2: <em> use the mole ratio to determine the moles of Fe</em>
the moles ratio of Al:Fe is 2:2= 1:1
therefore the moles of Fe is also = 9.5 x10 ^-4 moles
Step 3: <em> find the mass of Fe</em>
mass= moles x molar mass of Fe
from periodic table the molar mass of Fe= 56 g/mol
mass= 9.5 x10 ^-4 moles x 56 g/mol =0.0532 grams
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