Answer:
I don't understand what to do with this
To find the chemical formula of an ionic compound, the first step is to find the charge of the 2 ions. As given already, the charge of sodium ion is 1+, and carbonate ion has a charge of 2-. We can picture it like that: Sodium ion loses 1 electron and carbonate ion gains 2.
The next step is to find how the 2 ions can lose and gain electrons equally. In this case, since each Na ion only loses 1 electron, it cannot satisfy the need of one carbonate ion, since they need 2, not 1. Therefore, 2 Na ions can cover the need of one carbonate ion. So, the ratio of Na to CO3 ion should be 2:1.
Now just combine the 2 ions, positive one at the front, which makes it NaCO3, make sure you do not add the charge and notice that CO3 is a molecule itself so do not remove the 3. Now because the ratio is 2:1, so the final formula is Na2CO3, no need to add 1 if the ratio is 1.
Your answer should be Na2CO3.
Answer:
24.5
Explanation:
15/6.3 => 2.38 half lives passed.
.5^2.38 => 0.19198 decimal representation of the percentage that is left over after 2.38 half lives have passed.
0.19198 *128 = 24.5 mg of the material remaining.
Answer:
Potential energy is transformed to kinetic energy
Explanation:
Once a river is dammed it changes its physical and chemical structure. Damming also changes the biological communities associated with the river and its floodplain. When water is kept behind dams, seasonal flow patterns are usually lost.
A hydroelectric dam converts the potential energy stored in a water reservoir behind a dam to mechanical energy—mechanical energy is also known as kinetic energy. As the water flows down through the dam its kinetic energy is used to turn a turbine.
That would be a catalyst, it makes the reaction faster.
