Answer:
Hydrogen gas and a salt formed at the end of the reaction.
Explanation:
Hydrogen Gas has formed which inflated the balloon
Usually, metals and acids react to form a salt and Hydrogen Gas.
Here's what happened:
Zn (s) + 2HCl (aq) →
(aq) +
(g)
Cheers :)
In a neutral atom, the number of protons is equal to the number of electrons.
Given that the charge on the ion of the element is -1. This means that there is one electron more than the number of protons in the element.
The atomic number = Number of protons = 57 -1 = 56
Element with atomic number 56 is Barium.
Mass number of the element = Number of protons + Number of neutrons
= 56 + 80 = 136
So the identity of the species: 
Moles KClO₃ = 0.239
<h3>Further explanation</h3>
Given
Reaction
2KClO₃(s) ⇒2KCl(s) + 3O₂(g)
P water = 23.8 mmHg
P tot = 758 mmHg
V = 9.07 L
T = 25 + 273 = 298 K
Required
moles of KClO₃
Solution
P tot = P O₂ + P water
P O₂ = P tot - P water
P O₂ = 758 - 23.8
P O₂ = 734.2 mmHg = 0.966 atm
moles O₂ :
n = PV/RT
n = 0.966 x 9.07 / 0.082 x 298
n = 0.358
From equation, mol ratio KClO₃ : O₂ = 2 : 3, so mol KClO₃ :
= 2/3 x mol O₂
= 2/3 x 0.358
= 0.239
Answer:
The law of conservation of mass applies to both cases
When 50 g of sugar undergoes a physical change, say for example melting, the amount of sugar in the solution or melted form will also be 50 grams. This shows that the mass before and after the change was the same, in accordance to the law of conservation of mass. The mass stays the same.
When the magnesium strip is burned, this is a chemical reaction. The problem is that we only measure the mass of one of the substances involved in the reaction which is the magnesium strip, which makes it seem like the mass has increased. Actually, while burning, the magnesium combines with oxygen in the air. This oxygen was present before the reaction, we just did not measure it. And after the reaction it is present in the form of product. But the mass is still conserved.
Hope this helps!!:)