How many moles of H2 are produced?
How many liters of H2 are produced?
0.5 moles is required for the given reaction to occur. Mole is a constant that represents a certain amount of particles such as atoms, ions, or molecules.
It is the number or constant that represents a certain amount of particles such as atoms, ions, or molecules.
1 mole = particles.
Where,
- number of moles
- given mass = 13.5 g.
- molar mass = 26.98 g/mol.
Put the values in the formula,
Therefore, 0.5 moles is required for the given reaction to occur.
Learn more about Mole concept:
Answer:
1) 0.5 mol.
2) 0.75 mol.
3) 16.8 L.
Explanation:
1) How many moles of Al react?
n = mass / molar mass,
Mass of Al = 13.5 g.
Molar mass mass of Al = 26.98 g/mol.
∴ The number of moles of Al (n) = mass / molar mass = (13.5 g) / (26.98 g/mol) = 0.5 mol.
2) How many moles of H₂ are produced?
2Al + 6HCl → 2AlCl₃ + 3H₂.
Using the cross multiplication:
2.0 moles of Al → 3.0 moles of H₂, from the stichiometry,
0.5 mole of Al → ??? moles of H₂.
∴ The number of moles of H₂ are produced = (0.5 mole)(3.0 mole) / (2.0 mole) = 0.75 mol.
3) How many liters of H₂ are produced?
It is known that at STP, 1.0 mole of any gas occupies a volume of 22.4 L.
Using cross multiplication:
1.0 mole occupies → 22.4 L.
0.75 mole occupies → ??? L.
∴The number of liters of H₂ are produced = (0.75 mole)(22.4 L) / (1.0 mole) = 16.8 L.
B They both dissociate completely, with little or no reverse reactions.
C They both remain intact when placed in water, with no dissociation taking place.
D They both dissociate completely, with reverse reactions constantly taking place.
2 What happens when the kinetic energy of molecules increases so much that electrons are released by the atoms, creating a swirling gas of positive ions and negative electrons?
A Matter changes to a solid state.
B Matter changes to a liquid state.
C Matter changes to a plasma state.
D Matter changes to a gaseous state.
3 Consider a balloon that has a volume V. It contains n moles of gas, it has an internal pressure of P, and its temperature is T. If the balloon is heated to a temperature of 15.5T while it is placed under a high pressure of 15.5P, how does the volume of the balloon change?
A It doubles.
B It stays the same.
C It increases greatly.
D It decreases slightly.
1) Answer is: B They both dissociate completely, with little or no reverse reactions.
Some of strong acids: HNO₃(nitric acid), HCl(hydrochloric acid), H₂SO₄(sulfuric acid), HI(hydroiodic acid). Strong bases are: sodium hydroxide (NaOH), barium hydroxide (Ba(OH)₂).
For example, hydrochloric acid, completely dissociate in water and give large amount of hydrogen ions (H⁺): HCl(aq) → H⁺(aq) + Cl⁻(aq).
Sodium hydroxide completely dissociate in water:
NaOH(aq) → Na⁺(aq) + OH⁻(aq).
2) Answer is: C Matter changes to a plasma state.
Plasma is a an ionised gas with highly electrical conductivity.
In solid, molecules are closely packed, stiff and do not changes of shape or volume. Solid object (for example iron) does not take on the shape of its container.
Liquids have definite volume, but no fixed shape.
Gases (for example nitrogen and neon) not have definite volume and fixed shape, it depends on its container.
3) Answer is: B It stays the same.
p₁ = P; initial pressure.
p₂ = 15.5 P; final pressure.
V₁ = V: initial volume.
V₂ = ?: final volume.
T₁ = T; initial temperature.
T₂ = 15.5T; final temperature.
The combinated gas law: The volume of a given amount of gas is proportional to the ratio of its Kelvin temperature and its pressure: p₁·V₁/T₁ = p₂·V₂/T₂.
P·V/T = (15.5P · V₂) / 15.5 T.
V₂ = V₁ = V.
Answer:
1). B
2). C
3). B
Explanation:
Answer:The strongest base with concentration is .
Explanation:
Higher the pH value less will be the concentration of ion concentration and stronger will be the base.
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The strongest base with concentration is .