Answer:
1. Diagram C.
2. Diagram A.
Explanation:
1. Calcium atom, Ca has 20 protons and 20 electrons. On the other hand, Calcium ion, Ca^2+ has 20 protons and 18 electrons. This is true because the +2 charge on the calcium ion, Ca^2+ indicates that the calcium atom, Ca has loss 2 electrons.
From the above illustration we can say that calcium ion, Ca^2+ has the following:
Proton = 20
Electron = 18
Therefore, diagram C indicates calcium ion, Ca^2+.
2. Fluorine atom, F has 9 protons and 9 electrons. Fluoride ion, F¯ has 9 protons and 10 electrons. This is so because the –1 charge on the fluoride ion, F¯ indicates that the fluorine atom, F has gained 1 electron.
Thus, we can say that the fluoride ion, F¯ has the following:
Proton = 9
Electron = 10
Therefore, diagram A represent fluoride ion, F¯.
Balanced chemical equation:
* moles of oxygen
4 Al + 3 O2 = 2 Al2O3
4 moles Al -------------- 3 moles O2
9.30 moles Al ---------- moles O2
moles O2 = 9.30 * 3 / 4
moles O2 = 27.9 / 4 => 6.975 moles of O2
Therefore:
Molar mass O2 = 31.9988 g/mol
n = m / mm
6.975 = m / 31.9988
m = 6.975 * 31.9988
m = 223.19 of O2
Answer:
B. 1:2
Explanation:
Molar ratio depicts the relationship between the number of moles of two substances. The chemical equation in this question is as follows:
2H2 + O2 → 2H2O
This question is asking to identify the molar ratio of O2 to H2O in the equation. Since 1 mole of oxygen gas (O2) produces 2 moles of water (H2O). Hence, the O2 to H2O molar ratio is 1:2.
Answer:
When the electron changes levels, it decreases energy and the atom emits photons. The photon is emitted with the electron moving from a higher energy level to a lower energy level. The energy of the photon is the exact energy that is lost by the electron moving to its lower energy level.
Explanation:
Answer:
You can see that the line is going up and is curved in a positive direction.
Explanation:
When an object is speeding up, the acceleration is in the same direction as the velocity. Thus, this object has a positive acceleration.
