Explanation:
Reagents: Water , 1.0 M HCl, Conc. 
Metal-1 = Magnesium
Metal-2 = Sodium
Metal-3 = Silver
a) Out of these three metals sodium is a soft metal which can be easily cut with help of knife.Sodium metal reacts violently with water to form hydrogen gas and sodium hydroxide.

b) Out of magnesium and silver, magnesium metal reacts readily with HClto form magnesium chloride and hydrogen gas. Where as silver being noble metal doesn't get attacked by the HCl.

c) Silver is a noble metal. And noble metals only react with concentrated
that is nitric acid.

d) When few drops of HCl were added to the solution of silver and
. This will leads to the formation of nascent chloride which reacts with silver metal present in the solution to give silver chloride.


I agree with top guy C. and C makes most sense and sorry if I am wrong
pH ranges from 0 to 14, with 7 being neutral. pHs less than 7 are acidic while pHs greater than 7 are alkaline (basic).
Explanation:
If soil consists of more acidic nature then, it does not allow plant growth.
In that situation, treat the soil with (anti-acid which is nothing but) base.
When an acid reacts with a base, a neutralization reaction takes place and salt and water are formed in this reaction.
The equation is shown below:
acid+base-> salt +water
For example, if the soil has more sulphuric acid traces then, it should be treated with lime.

Hey there!
pH = - log [ H⁺ ] = 3.52
[ H⁺ ] = 10^-pH
[ H⁺] = 10^ ( -3.52 )
[H⁺] = 3.02*10⁻⁴ M
[HA] =0.175 M
Therefore:
Ka = [ H⁺]* [A⁻] / [ HA]
Ka = (3.02*10⁻⁴)² / 0.175
Ka = 9.1204*10⁻⁸ / 0.175
Ka = 5.2*10⁻⁷
Hope that helps!