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2 years ago

I NEED HELP PLEASE, THANKS!

Chemistry

1 answer:

ira [324]2 years ago

6 0

Answer:

About 0.652

Explanation:

Because the reaction is balanced, we can go straight to the next step. The molar mass of potassium is about 39.098, while the molar mass of hydrogen gas is 2 and the molar mass of water is 18. Therefore, 25.5g of potassium would be about 0.652 moles, and 220 grams of water would be about 12.222 moles, making potassium the limiting reactant. Since there is a single unit of each compound on both sides of the equation, there would be an equal amount of moles of potassium and hydrogen, and therefore about 0.652 moles of hydrogen gas would be produced. Hope this helps!

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Answer:

a) Ammonium ion: NH₄⁺, ammonia: NH₃.

b)Magnesium sulfide: MgS, magnesium sulfite: MgSO₃, magnesium sulfate: MgSO₄.

c) Chloric acid: HClO₃, chlorous acid HClO₂.

d) Cupric bromide: CuBr₂, cuprous bromide: CuBr.

Explanation:

a) Ammonia is the neutral substance, which as molecular formula NH₃ when it gains a proton, it becomes the ammonium ion NH₄⁺.

b) In the name of salts, first, it comes the cation name, in this case, all the cations are the magnesium (Mg²⁺). The ions of sulfur can be oxidized or not, the termination "ide" indicates the non-oxidized ion (S⁻²), "ite" the less oxidized (SO₃⁻²), and "ate" the more oxidized (SO₄⁻²). To do the molecular formula, the charges are replaced without the signals and put down. If they are equal, the number is not put.

Magnesium sulfide: MgS

Magnesium sulfite: MgSO₃

Magnesium sulfate: MgSO₄

c) The acids can be oxidized or not, when it has no oxygens, the name is given "hydro" + the anion name, as hydrochloric acid (HCl). When there's oxygen in the molecule, the more oxidized is name as "'per" + anion name + "ic", the second more oxidized as anion name + "ic", the second less oxidized as anion name + "us", and the less oxidized as "hypo" + anion name + "us". In this case:

chloric acid: HClO₃

chlorous acid HClO₂

d) The salts of copper are named depends on the oxidation number of the cupper. The one with a higher oxidation number( +2) is called cupric, and the other (+1), cuprous. Thus:

cupric bromide: CuBr₂ (oxidation number = +2)

cuprous bromide: CuBr (oxidation number = +1)

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