Answer:
Current, I = 8 A
Explanation:
We have,
Voltage, V = 160 V
Resistance, R = 20 ohms
It is required to find the current. The relation between current, voltage and resistance is called Ohm's law. It is given as :

I = current

So, the value of current is 8 A.
Answer:
A cation is an ion with fewer electrons than protons. Therefore, it has a positive charge. The electric charge on a proton is equal in amount to the charge on an electron. Anions are atoms or radicals (groups of atoms), that have gained electrons. Since they now have more electrons than protons, anions have a negative charge. Halogens always form anions, alkali metals and alkaline earth metals always form cations. Most other metals form cations (e.g. iron, silver, nickel), whilst most other nonmetals typically form anions (e.g. oxygen, carbon, sulfur).
Explanation:
An anion and cation cannot be specifically found on the periodic table.
Answer:
The mass percent of copper as element is the same.
Explanation:
First of all we need the reaction that is presented below:
→ 
The mass percent of copper (Cu) as element is the same because of during the reaction the element only transform its nature from copper carbonate (
) to copper oxide (
), the latter is a solid and will remain in the system.
On the other hand, you will note that the global percentage mass will be small because of the reaction produce (
) that is a gas and this one will escape for the system.
Have a great day!
D = m / V
D = 2790 g / 205 mL
D = 13.60 g/mL