Answer:
Hydrogen carbonate is an acid, sodium Sulfate is a salt.
Explanation:
Hydrogen carbonate is a weak acid because it will partially ionize in water while sodium sulfate is a neutral salt which is formed when neutralization of acid and base takes place
Answer: The correct answer is C.
Explanation: Frictional force is the contact force which resists the motion of one surface on another.
Mathematically,

where,
f = frictional force
= Coefficient of friction
N = normal force acting on a body
We need to find the ratio of force of sliding friction ( which is a type of frictional force) and the normal force acting on an object. This will be equal to coefficient of friction.

Answer:
d. NaOH Sodium hydroxide soluble
I believe that The answer is
Hydrogen peroxide is a powerful oxidizer. When exposed to sunlight it quickly decomposes to form water and oxygen as given by the following equation.
2H2O2(aq) → 2H2O(l) + O2(g)
Hydrogen peroxide is commercially available as a 30% w/w solution, which is the concentration that would facilitate the above reaction. This implies that the concentration would be 30 g of H2O2 in 100 g of the solution.