Answer:
open system
Coffee held in a cup is an open system because it can exchange matter water vapors and energy heat with the surroundings.
Answer:
+3
Explanation:
The oxygen all have a -2 oxidation state. (peroxides are exceptions)
The chemical structure is symmetrical. Both carbon are equivalent.
2 (oxidation state of carbon) + 4 (oxidation state of oxygen) = charge of ion.
2 (oxidation state of carbon) + 4 (-2) = -2
oxidation state of carbon = +3
<u>Answer:</u> The given amount of iron reacts with 9.0 moles of
and produce 6.0 moles of 
<u>Explanation:</u>
We are given:
Moles of iron = 12.0 moles
The chemical equation for the rusting of iron follows:

By Stoichiometry of the reaction:
4 moles of iron reacts with 3 moles of oxygen gas
So, 12.0 moles of iron will react with =
of oxygen gas
- <u>For iron (III) oxide:</u>
By Stoichiometry of the reaction:
4 moles of iron produces 2 moles of iron (III) oxide
So, 12.0 moles of iron will produce =
of iron (III) oxide
Hence, the given amount of iron reacts with 9.0 moles of
and produce 6.0 moles of 
Answer:

Explanation:
The fission reaction taking place given in the question is:

The mass is conserved in the reaction.
So,
235 + 1 = A + 94 + 3×1
A = 139 g/mol
Also, number o protons remain same. So,
92 = Z + 36
Z = 56
The isotopic symbol is 
Answer:
so like Each of the five states of matter collectively made up all the "stuff" that's in the universe- — everything that takes up space and has mass is matter,and All matter is made up of atoms and in turn made up of protons and neutrons and electrons.
Explanation: hope this helps