<h2>Hardness, lustre, and colour.</h2>
Explanation:
These Rocks shown in photographs are made of different types of minerals which have properties as follows:
●The color of the rock is grey, brown and yellow after it is ground into a powder its color is streak.
● The lustre of the rock tells how shiny the rocks are.
● Other properties include hardness, texture, shape, and size.
Answer : The current passing between the electrodes is, 
Explanation :
First we have to calculate the charge of sodium ion.

where,
q = charge of sodium ion
n = number of sodium ion = 
e = charge on electron = 
Now put all the given values in the above formula, we get:

Now we have to calculate the charge of chlorine ion.

where,
q' = charge of chlorine ion
n = number of chlorine ion = 
e = charge on electron = 
Now put all the given values in the above formula, we get:

Now we have to calculate the current passing between the electrodes.



Thus, the current passing between the electrodes is, 
Answer:
there are literally millions - alkanes, alkenes, alkynes, alcohols, esters, carboxylic acids... to name but a few.
Explanation:
Aqueous nitric acid and aqueous ammonia reacts to form ammonium nitrate
HNO₃(aq)+NH₃(aq) = NH₄NO₃(aq)
HNO₃ +NH3 = NH₄ (+) + NO₃ (-)
Therefore the net ionic equation will be;
H⁺(aq) + NH₃ = NH₄⁺ (aq)