Answer:
Half-reactions:
Cr³⁺ + 1e⁻ → Cr²⁺; Zn → Zn²⁺ + 2e⁻
Net ionic equation:
2Cr³⁺ + Zn → 2Cr²⁺ + Zn²⁺
Explanation:
The Cr³⁺ is reduced to Cr²⁺:
<h3>
Cr³⁺ + 1e⁻ → Cr²⁺ -Half-reaction 1-</h3>
Zn is oxidized to Zn²⁺:
<h3>
Zn → Zn²⁺ + 2e⁻ -Half-reaction 2-</h3>
Twice the reduction of Cr:
2Cr³⁺ + 2e⁻ → 2Cr²⁺
Now this reaction + Oxidation of Zn:
2Cr³⁺ + 2e⁻ + Zn → 2Cr²⁺ + Zn²⁺ + 2e⁻
<h3>2Cr³⁺ + Zn → 2Cr²⁺ + Zn²⁺ - Net ionic equation</h3>
The ions formed are NH4(+) and S(2-)
The dissolution reaction of (NH4) 2S in water is as follows:
(NH4) 2S ==> 2 NH4 (+) + S (2-).
Ammonium sulfide is the ammonium salt of hydrogen sulfide. It has the formula (NH4) 2S and belongs to the sulfide family.
It is a relatively unstable compound (crystals decomposing at -18 ° C, but exists and is more stable in aqueous solution.) With a pKa exceeding 15, the hydrosulfide ion cannot be significantly deprotonated by ammonia. Thus, such solutions consist mainly of a mixture of ammonia and hydrosulphide of ammonium, it has a smell, close to that of hydrogen sulfide, and its aqueous solutions can be precisely by emitting H2S.
Answer:
30.8 g of water are produced
Explanation:
First of all we need the equation for the production of water:
2H₂ + O₂ → 2H₂O
2 moles of hydrogen react with 1 mol of oxygen in order to produce 2 moles of water.
As we assume, the oxygen in excess, we determine the moles of H₂.
1.03ₓ10²⁴ molecules . 1 mol/ 6.02ₓ10²³ molecules = 1.71 moles
Ratio is 2:2, so 1.71 moles will produce 1.71 moles of water
Let's convert the moles to mass: 1.71 mol . 18g / 1mol = 30.8 g of water are produced
Answer:
A liquid changing to a gas is considered a physical change because it involves a change in one or more physical properties, but no change in the fundamental components that make up the substance.