Answer:
MoO₃
Explanation:
To solve this question we must find the moles of molybdenum in Mo2O3. The moles of Mo remain constant in the new oxide. With the differences in masses we can find the mass of oxygen and its moles obtaining the empirical formula as follows:
<em>Moles Mo2O3 -Molar mass: 239,878g/mol-</em>
11.79g * (1mol / 239.878g) = 0.04915 moles Mo2O3 * (2mol Mo / 1mol Mo2O3) = 0.09830 moles Mo
<em>Mass Mo in the oxides:</em>
0.09830 moles Mo * (95.95g/mol) = 9.432g Mo
<em>Mass oxygen in the new oxide:</em>
14.151g - 9.432g = 4.719g oxygen
<em>Moles Oxygen:</em>
4.719g oxygen * (1mol/16g) = 0.2949 moles O
The ratio of moles of O/Mo:
0.2949molO / 0.09830mol Mo = 3
That means there are 3 moles of oxygen per mole of Molybdenum and the empirical formula is:
<h3>MoO₃</h3>
Answer:
1.35 moles of O²⁻
21.6 grams of O²⁻
Explanation:
We know that the charge on Aluminium ion is +3 (i.e. Al³⁺) while, the charge on Oxide ion is -2 (i.e. O²⁻). Therefore, the overall neutral Al₂O₃ compound has 2 Al³⁺ ions and 3 O²⁻ ions. Since, we can say that,
1 mole of Al₂O3 contains = 3 moles of O²⁻ ions
So,
0.450 moles of Al₂O₃ will have = X g of O²⁻
Solving for X,
X = 0.450 mol × 3 mol ÷ 1 mol
X = 1.35 moles of O²⁻
As the mass of an atom is mainly due to the presence of protons and neutrons hence, the addition of two electrons (-ve 2 shows two gained electron) to Oxygen will make a negligible change to the atomic masss of Oxygen because electron is said to be almost 1800 times lighter than proton. Hence, the ionic mass of O²⁻ will be 16 g/mol and the mass of given moles is calculated as,
Mass = Moles × Ionic Mass
Mass = 1.35 mol × 16 g/mol
Mass = 21.6 g
Answer is: glycerol because it is more viscous and has a larger molar mass.
Viscosity depends on intermolecular interactions.
The predominant intermolecular force in water and glycerol is hydrogen bonding.
Hydrogen bond is an electrostatic attraction between two polar groups in which one group has hydrogen atom (H) and another group has highly electronegative atom such as nitrogen (like in this molecule), oxygen (O) or fluorine (F).
Answer: 225 joules.
Explanation:
If this a one dimension problem, this is the motion is in the same direction of the force, the equation for work is:
Work = distance × force
⇒ Work = 15 m × 15 N = 225 joules.
This is a special case of the general equation
Work = |F| |displacement| cosine (angle between the force and displacement)
When force and displacement are in the same direction, the angle is 0, so cos(0) = 1. This is the two vectors are parellel and the work is just the product of the two magnitudes (force and distance)
