Answer:
A neutral particle made of an electron and hole
Explanation:
Exciton
It is the combination of an electron and a hole ( hole refers to the vacancy of an electron ) . And , as both the electron and the hole have the same charge but the polarity is opposite , the combination will lead to a neutral compound , i.e. , Exciton have no charge and so neutral .
It is free to move in the nonmetallic crystal and since it charge less , it is difficult to detect it directly .
Answer:
Maybe or maybe not (not sure)
Explanation:
A displacement reaction is a type of reaction where one element is displaced by another from a compound.
In the case of magnesium and lead nitrate, magnesium is more reactive than lead. Therefore, it will displace lead from lead nitrate to form magnesium nitrate and lead.
The reaction can be represented as:
Mg(s) + Pb(NO3)2(aq) → Mg(NO3)2(aq) + Pb(s)
Another answer could be;
A displacement reaction does not take place in 'magnesium + lead nitrate' because magnesium is more reactive than lead.
