Answer:
a. The student performed the splint test incorrectly. He should of observed a popping sound when the splint was placed in the test tube.
Explanation:
It is given that a student performed an experiment where he dropped a nickel metal in to HCl solution. He observed the reaction and performed a splint test in the test tube that is filled with a gas which is formed while Nickle is dropped into the solution of HCl.
But the experiment that the student performed was incorrect. He must have observed the popping sound when the splint was placed in the test tube.
When the splint was added to the gas splint flared up. The hydrogen gas pops out when exposed to the flame.

Thus the correct option is (a).
Answer:
from 10-14
Explanation:
the pH of potassium hydroxide is extremely high and is a strong base although the exact value depends on the concentration of the base in water.
Answer:
F = 30 N
Explanation:
Given data:
Mass of toy train = 1.5 kg
Acceleration of train = 20 m/s²
Amount of force acting on it = ?
Solution:
The net force on object is equal to the its mass multiply by its acceleration.
Formula:
F = ma
F = force
m = mass
a = acceleration
Now we will put the values in formula.
F = 1.5 kg × 20ms⁻²
F = 30 kg.ms⁻²
kg.ms⁻² = N
F = 30 N
Answer:
If a metal and metal solution react, the more reactive metal will displace the less reactive metal from solution. If the metal in solution you start with is formed from a more reactive metal than the metal to be added, no reaction will occur.