When it begins to have a chemical affect
Things that float or sink
Answer:
Zinc metal reacts with hydrochloric acid according to the following balanced equation:
Zn(s)+2HCl(aq)→ZnCl2(aq)+H2(g)Zn(s)+2HCl(aq)→ZnCl2(aq)+H2(g)
When 0.122 gg of Zn(s)Zn(s) is combined with enough HClHCl to make 50.9 mLmL of solution in a coffee-cup calorimeter, all of the zinc reacts, raising the temperature of the solution from 21.5 ∘C∘C to 24.2 ∘C∘C.
Explanation:
Answer:
option (d) is false.
Explanation:
Acid dissociation equilibrium of HCN is represented as-

Acid dissociation constant,
, is represented as-
![K_{a}=\frac{[H^{+}][CN^{-}]}{[HCN]}](https://tex.z-dn.net/?f=K_%7Ba%7D%3D%5Cfrac%7B%5BH%5E%7B%2B%7D%5D%5BCN%5E%7B-%7D%5D%7D%7B%5BHCN%5D%7D)
where species inside third bracket represents equilibrium concentrations of respective species
So, evidently, presence of excess
(or NaCN) in solution will combine with
to produce HCN. Hence
will be larger that it would be if only the HCN solution were present.
According to Le-chatlier principle, addition of HCN will shift equilibrium towards right and addition of NaCN will shift equilibrium towards left to keep constant
value at a particular temperature.
NaOH gives acid-base reaction with HCN to produce NaCN and water. So, addition of NaOH will increase concentration of
and decrease concentration of HCN
Answer:
2
Explanation:
Covalent bonding occurs when pairs of electrons are shared by atoms. Atoms will covalently bond with other atoms in order to gain more stability, which is gained by forming a full electron shell. By sharing their outer most (valence) electrons, atoms can fill up their outer electron shell and gain stability.