Answer:A
Explanation:2 phosphorus and 2 oxygen
Answer:
32.23 to 4 significant figures.
Explanation:
The molar mass of the element is the mass of 6.022 * 10^23 atoms (Avogadro's number).
So by proportion it is 6.022 * 10^23 * 3.88 / 7.25 * 10^22
= 32.23 to 4 significant figures.
Answer:
C. An external voltage source
Explanation:
An electrolytic cell converts electrical energy from an external voltage source into chemical energy that drives a reaction.
The external voltage source is usually a battery. This energy form generated from the battery helps to drive chemical reactions.
The process involves the decomposition of an ionic compound by means of current passed into the aqueous or molten form of the compound through conductors known as electrodes.
Its the complete transfer of valence electrons between atoms
For a closed system, you need two things:
1) a conservation of mass within the boundaries of the system
2) the ability to freely exchange energy to & from the "closed" system with a surrounding external system
So, the answer is <u><em>never</em></u>, since your defining the "system" as the water within the bathtub, and an open bathtub is exposed to evaporation, which is not conserving mass within the defined "system".