Will mark the best answer as branliest!
answer and explain!
1. combine iron and copper (ii) sulfate solution. (hint: iron will form the iron (iii) ion) fe + cuso4 →
2. combine lead (ii) nitrate and potassium iodide solutions. pb(no3)2+ kl →
3. electrolysis (splitting) of water. h2o →
4. burning magnesium. mg + o2 →

1. 2Fe + 3CuSO₄ →  Fe₂(SO₄)₃ + 3Cu.

2. Pb(NO₃)₂+ 2Kl →  PbI₂ + 2KNO₃.

3. Mg + 2HCl →  MgCl₂ + H₂.

4. H₂O →  H₂ + 1/2O₂.

5. 2Mg + O₂ → 2MgO.

2Fe + 3CuSO₄ →  Fe₂(SO₄)₃ + 3Cu.

It is a redox reaction including replacing Cu with Fe and changing their oxidation states.

That Fe replaces Cu and resulting in ferric sulfate.

2.Combine lead (II) nitrate and potassium iodide solutions.

Pb(NO₃)₂+ 2Kl →  PbI₂ + 2KNO₃.

It is a double replacement reaction that lead nitrate reacts with potassium iodide resulting in lead iodide and potassium nitrate.

3.Combine magnesium metal and hydrochloric acid solution.

Mg + 2HCl →  MgCl₂ + H₂.

It is a dissolution reaction that HCl dissolve Mg and resulting in Magnesium chloride and hydrogen gas is evolved.

4.Electrolysis (splitting) of water.  

H₂O →  H₂ + 1/2O₂.

Water electrolysis resulting in splitting of water to produce hydrogen and water.

5.Burning magnesium.

2Mg + O₂ → 2MgO.

It is a combustion reaction that Mg is burned with oxygen to produce magnesium oxide.

Explanation:1.Combine iron and copper (II) sulfate solution. (Hint: Iron will form the iron (III) ion)

2Fe + 3CuSO₄ →  Fe₂(SO₄)₃ + 3Cu.

It is a redox reaction including replacing Cu with Fe and changing their oxidation states.

That Fe replaces Cu and resulting in ferric sulfate.

2.Combine lead (II) nitrate and potassium iodide solutions.

Pb(NO₃)₂+ 2Kl →  PbI₂ + 2KNO₃.

It is a double replacement reaction that lead nitrate reacts with potassium iodide resulting in lead iodide and potassium nitrate.

3.Combine magnesium metal and hydrochloric acid solution.

Mg + 2HCl →  MgCl₂ + H₂.

It is a dissolution reaction that HCl dissolve Mg and resulting in Magnesium chloride and hydrogen gas is evolved.

4.Electrolysis (splitting) of water.  

H₂O →  H₂ + 1/2O₂.

Water electrolysis resulting in splitting of water to produce hydrogen and water.

5.Burning magnesium.

2Mg + O₂ → 2MgO.

It is a combustion reaction that Mg is burned with oxygen to produce magnesium oxide.

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.