Answer:
Explanation:
Mass of compound A = 25g
Mass of compound B = 40g
Mass of final mixture = 55g
What happens to the missing mass?
According to the law of conservation of mass, in chemical reaction, matter is transformed from one form to another but cannot be created nor destroyed.
We expect the final mass of the mixture and that of the reacting compounds to be the same but the opposite is the case.
There is a mass loss which typifies most chemical reaction.
The reason for this is that some of the masses must have been lost by the production of gaseous species which are unaccounted for.
The missing mass:
Total mass expected = mass of A + mass of B = 25 + 40 = 65g
Missing mass = expected mass - mass of final mixture = 65 - 55 = 10g
Answer:
2Li(s) + 2H₂O(ℓ) ⟶ 2Li⁺(aq) + 2OH⁻(aq) + H₂(g)
Explanation:
An ionic equation uses the symbols (aq) [aqueous] to indicate molecules and ions that are soluble in water, (s) [solid] to indicate insoluble solids, and (ℓ) to indicate substances (usually water) in the liquid state.
In this reaction, solid lithium reacts with liquid water to form soluble lithium hydroxide and gaseous hydrogen
.
1. Molecular equation
2Li(s) + 2H₂O(ℓ) ⟶ 2LiOH(aq) + H₂(g)
2. Ionic equation
Lithium hydroxide is a soluble ionic compound, so we write it as hydrated ions.
2Li(s) + 2H₂O(ℓ) ⟶ 2Li⁺(aq) + 2OH⁻(aq) + H₂(g)
Every electron carries one elementary negative charge. Concerning mass,
it takes roughly 1,840 electrons to make enough mass for 1 proton or 1 neutron.
Electrons don't necessarily have to stay connected to an atom, but when they do,
they circle the nucleus.
So you should select (C): ==> Negative, ==> light, ==> circling the nucleus.
Answer:
VP (solution) = 171.56 mmHg
Explanation:
Vapor pressure of pure solvent(P°) - Vapor pressure of solution (P') = P° . Xm
Let's replace the data:
173.11 mmHg - P' = 173.11 mmHg . Xm
Let's determine the Xm (mole fraction for solute)
Mole fraction for solute = Moles of solute / Total moles
Total moles = Moles of solute + moles of solvent.
Let's determine the moles
Moles of solvent → 623.4 g / 119.4 g/mol = 5.22 moles
Moles of solute → 9.322 g / 180.1 g/mol = 0.052 moles
Total moles = 0.052 + 5.22 = 5.272 moles
Xm = 0.052 moles / 5.272 moles = 0.009 → 9/1000
173.11 mmHg - P' = 173.11 mmHg . 9/1000
P' = - (173.11 mmHg . 9/1000 - 173.11 mmHg)
P' = 171.56 mmHg
