First a balanced reaction equation must be established:

→

Now if mass of aluminum = 145 g
the moles of aluminum = (MASS) ÷ (MOLAR MASS) = 145 g ÷ 30 g/mol
= 4.83 mols
Now the mole ratio of Al : O₂ based on the equation is 4 : 3
[
4Al +
3 O₂ → 2 Al₂O₃]
∴ if moles of Al = 4.83 moles
then moles of O₂ = (4.83 mol ÷ 4) × 3
=
3.63 mol (to 2 sig. fig.)
Thus it can be concluded that
3.63 moles of oxygen is needed to react completely with 145 g of aluminum.
Answer:
Amount of heat energy released by light bulb = 25 joules
Explanation:
Given:
Energy receive by light bulb = 100 Joules
Energy released by light bulb as light energy = 75 Joules
Find:
Amount of heat energy released by light bulb
Computation:
We know that, energy is neither be created nor destroys
So,
Using Law of conservation of energy
Energy receive by light bulb = Energy released by light bulb as light energy + Amount of heat energy released by light bulb
100 = 75 + Amount of heat energy released by light bulb
Amount of heat energy released by light bulb = 100 - 75
Amount of heat energy released by light bulb = 25 joules
Answer:
A. Felsic igneous rocks are less dense than mafic igneous rock
Explanation:
"Felsic rocks are composed of larger quantities of silicates and therefore are less dense. Felsic magma is less dense and more viscous than mafic magma." - study.com
Of the three sources listed, geothermal energy
is the least dependent on the weather.
(Once it's installed and running, that is.)
Answer: im pretty sure its D
Explanation: