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!
One atom of carbon weighs exactly 12/6.022x10^23 = 1.9927x10^-23 grams<span>.</span>
Answer:
A. Warning
Explanation:
Out of all said choices, the best choice would be warning since it would fit the sentence the most.
"A Warning notifies you that danger is present." compared to:
"A Hazard notifies you that danger is present."
"A Safety notifies you that danger is present."
"A Danger notifies you that danger is present."
C. Represents an oxidation-reduction reaction
H2SO4 + 2RbOH -> Rb2SO4 + 2H2O
If you want an explanation, keep reading.
In the first portion, there are two hydrogen ions and four sulfate ions.
The second portion has one rubidium ions and one hydroxide ion.
On the other side of the equation, in order to keep those two rubidiums balanced, you'll need to add a two at the beginning of the second portion, but in that process you are giving a second hydroxide value.
Back to the right side, there is there is water (H2O).
On the first portion, there were two hydrogen ions. The second portion also has two hydroxides because of the value change (adding the two to the front).
So on the fourth portion, you'd have to add another two so you could balance the four hydrogen ions (H2 and 2OH) and the two oxygen ions (2OH).
I hope this was easy to understand.
