Chemistryyy (1 Viewer)

[leehuan]

We have 2 oxygen atoms in the O2 molecule?

They each gain 2.

[This is NOT what happens: O + 4electrons -> O(4-)]

 

[drsabz101]

Ohhh that makes sense. Thanks

 

[drsabz101]

In the reaction why does the oxygen gas go from a gaseous state to a solid ?

 

[leehuan]

CaO is a compound. There is no more "oxygen" molecule there's only calcium oxide.

(atom means nothing, atoms build up elements and compounds and the elements/compounds are the species)

 

[drsabz101]

Is it true tin and water cannot react? Why though

 

[Shuuya]

Is it true tin and water cannot react? Why though

Tin reacts with steam (gaseous water)

Sn(s) + 2 H2O(g) -> SnO2(s) + 2 H2(g)

In metal + steam reactions, metal oxide + hydrogen gas is formed rather than metal hydroxide + hydrogen gas

This is because Tin is a relatively unreactive metal at room temperature (so does not readily react with water/oxygen) , and higher temperatures are required for a reaction to occur, where water becomes steam.

 

[drsabz101]

Thnx again

 

[Shuuya]

Thnx again

No worries

 

[leehuan]

Tin reacts with steam (gaseous water)

Sn(s) + 2 H2O(g) -> SnO2(s) + 2 H2(g)

In metal + steam reactions, metal oxide + hydrogen gas is formed rather than metal hydroxide + hydrogen gas

This is because Tin is a relatively unreactive metal at room temperature (so does not readily react with water/oxygen) , and higher temperatures are required for a reaction to occur, where water becomes steam.

True also for aluminium

Reactions with water are useful as they can be used to determine the reactivity series of metals.

 

[drsabz101]

Okay so I am going to post up my answer for the reaction of potassium and hcl acid let me know r/w

 

[drsabz101]

k(s) + 2HCL+ -> 2KCL aq + H2 (g)

 

[Shuuya]

k(s) + 2HCL+ -> 2KCL aq + H2 (g)

Almost Correct! Just a balancing error:

2K(s) + 2HCl(aq) ---> 2KCl(aq) + H2(g)

 

[drsabz101]

K I am finally getting somewhere haha

 

[drsabz101]

Okay ! Another q. Sorry this is like a chem marathon for me ^^

How do I balance

Ni(g) + H20(l) -> Ni(OH)2 + H2 (g)

 

[Silky_Smooth]

How do I balance

Ni(g) + H20(l) -> Ni(OH)2 + H2 (g)

Ni(g) + 2H2O(l) -> Ni(OH)2 + H2(g)

 

[drsabz101]

Thnx . Just wanted to know how to tell which elements DON'T react with oxygen by looking at the periodic table

 

[leehuan]

A lot of elements react with oxygen actually. That one's ambiguous.

 

[drsabz101]

what about water?

 

[drsabz101]

Like for example lead and water have no reaction, but how can u tell from looking straight from the table

 

[drsabz101]

And what does it mean if a certain metal never 'displaces' itself