5 moles of H2
..............
Answer: 8.7 grams
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number 
of particles.
To calculate the moles, we use the equation:
As oxygen is in excess, Aluminium is the limiting reagent and limits the formation of products.
According to stoichiometry:
4 moles of aluminium give = 2 moles of 
Thus 0.17 moles of aluminium give=
Mass of 
Thus the mass of is 8.7 grams
D) Contain Chemical bonds.
Explanation:
When a metal replaces another metal in solution, we say such a reaction has undergone a single displacement reaction.
In such a reaction, metal higher up in the activity series replaces another one due to their position.
To known the metal or metals that will replace the given copper, we need to reference the activity series of metals.
Every metal higher than copper in the series will displace copper from the solution.
So, there metals are: potassium, sodium, lithium, barium, strontium etc.
Answer:
salt bridge balances the charge when electrons move from one half cell to another half cell.
Explanation:
Explanation: A salt bridge balances the charge when electrons move from one half cell to another half cell. During this process the salt bridge uses its electrolyte solution which further helps in balancing charges in both the half cells. ... Therefore, for each electrochemical cell a new salt bridge is used.
