Answer:
872.28 kJ/mol
Explanation:
The heat released is:
ΔH = C*ΔT
where ΔH is the heat of combustion, C is the heat capacity of the bomb plus water, and ΔT is the rise of temperature. Replacing with data:
ΔH = 9.47*5.72 = 54.1684kJ
A quantity of 1.922 g of methanol in moles are:
moles = mass / molar mass
moles = 1.992/32.04 = 0.0621 mol
Then the molar heat of combustion of methanol is:
ΔH/moles = 54.1684/0.0621 = 872.28 kJ/mol
Answer:
being stationary relative to a particular frame of reference or another object; when the position of a body with respect to its surroundings does not change with time it is said to be at rest
Explanation:
The boiling point of a substance is a physical property.
A physical property of a material or substance is one that can be observed without changing or altering the composition of the material.
Examples are mass, Density, Color, solubility, boiling point, melting point .
A chemical property of a substance is one that describes how the material changes into a completely different substance and is observed only during a chemical reaction.
Examples of chemical properties include types of chemical bonds, heat of combustion, reactivity with other metals, oxidation state and enthalpy of formation.
Answer:
52.8 g of O2.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
4Al + 3O2 —> 2Al2O3
From the balanced equation above,
4 moles of Al reacted with 3 moles of O2 to produce 2 moles of Al2O3
Next, we shall determine the number of mole of O2 needed to react with 2.2 moles of Al. This can be obtained as follow:
From the balanced equation above,
4 moles of Al reacted with 3 moles of O2.
Therefore, 2.2 moles of Al will react with = (2.2 × 3)/4 = 1.65 moles of O2.
Thus, 1.65 moles of O2 is needed for the reaction.
Finally, we shall determine the mass of O2 needed as shown below:
Mole of O2 = 1.65 moles
Molar mass of O2 = 2 × 16= 32 g/mol
Mass of O2 =?
Mole = mass/Molar mass
1.65 = mass of O2 /32
Cross multiply
Mass of O2 = 1.65 × 32
Mass of O2 = 52.8 g
Therefore, 52.8 g of O2 is needed for the reaction.
