Answer:
decrease the volume of the cylinder.
Explanation:
In order to be able to solve this question we have to understand what Boyle's law is. According to Boyle's law; at constant temperature the pressure of a given mass of gas is inversely proportional to to its volume.
The Boyle's law shows us the relationship between the pressure and the volume. So, the Important thing to note hear is that if the volume in a container is decreased then the pressure will increase (and vice versa) due to the fact that as the volume decreases the particles in that container makes more collision which will make the pressure to increase.
Since, the piston is moveable it means that we can decrease and increase the volume in the cylinder. So, if the decrease the volume of the cylinder then we will have an increase in the pressure of the gas below the piston.
Answer: Magnesium and Bromine/MgBr2 = Ionic compounds
Explanation: When atoms form together they can form between Ionic Compounds and molecules; this could depend on if they're joined by Covalent bonds as well because when atoms form with Covalent bonds, it forms Molecules.
Answer: False
Explanation:
Electrons are the smallest of the three particles that make up atoms. Electrons are found in shells or orbitals that surround the nucleus of an atom. Protons and neutrons are found in the nucleus. They group together in the center of the atom.
The gas particles move faster.
Answer : The correct option is, (B)
Explanation :
Balance equation : Balanced equation are those equation in which the number of atoms of each element and the total charge must be same on products side and reactants side.
In the given options, only option (B) equation has correct formula and also a balanced equation.

while the other options has incorrect formulas and also an unbalanced equations.
The correct equation for option A is, 
The correct equation for option C is, 
The correct equation for option D is, 
Hence, the correct answer is, (B) 