Answer:
2.5 moles of Al
Explanation:
We'll begin by calculating the number of mole in 127 g of Al₂O₃. This can be obtained as follow:
Mass of Al₂O₃ = 127 g
Molar mass of Al₂O₃ = 101.961 g/mol
Mole of Al₂O₃ =?
Mole = mass / molar mass
Mole of Al₂O₃ = 127 / 101.961
Mole of Al₂O₃ = 1.25 mole
Finally, we shall determine the number of mole of Al that reacted. This can be obtained as follow:
4Al + 3O₂ —> 2Al₂O₃
From the balanced equation above,
4 moles of Al reacted to produce 2 moles of Al₂O₃.
Therefore, Xmol of Al will react to produce 1.25 moles of Al₂O₃ i.e
Xmol of Al = (1.25 × 4)/2
Xmol of Al = 2.5 moles.
Thus, 2.5 moles of Al is needed for the reaction.
Answer:
Evaporation
Explanation:
Evaporation involves a liquid becoming a gas and sublimation is the change of a solid directly to a gas. Phase changes require either the addition of heat energy or subtraction of heat energy .
Answer:
Source, processing and distribution are the components of water system.
Explanation:
There are three parts of water system i. e. the source, the processing and distribution. Water is extracted from a source such as underground water, lake or river etc. After extraction this water is transported to the processing unit where it can be purified and after purification it is distributed to all places where it is needed. Potential energy is a form of energy that flows through this water system because the water is extracted from a depth and we know that depth and height refers to potential energy.
It is energetically favorable for all atoms to have a complete outer
electron shell. Loosely, the atoms on the left hand side of the periodic
table only have a few extra electrons in their outer shell so it is
energetically favorable for them to lose them. The atoms on the right
hand side of the periodic table almost have enough electrons in their
outer shell and so they have a tendency to gain them.
Once electrons have left an electron shell, an atom will have a positive
charge because it has more protons (positive charges) than electrons
(negative charges). Similarly, an electron which has gained electrons to
complete its outer shell will have a negative charge because it now has
more electrons (negative charge) than protons (positive charge).
Answer:
I think that gravity can be considered a force.
Explanation:
As the object falls, it moves faster and faster. Gravity is considered a universal force because it acts between any two masses anywhere in the universe. For example, there is a gravitational pull between the Sun and the Moon. Even small masses attract one another.
Hope this helped! :)
