Atoms make up the mass of all materials
Atoms cannot be created or destroyed
So in a balanced chemical equation, all atoms are accounted for, and therefore all mass is accounted for and conserved.
Answer:
answer is b
use pv=nRT
p directly proportional to moles(n)
p1/p2=n1/n2
p/p2=n/2n
p2=2p
Answer:
The element iodine forms an anion with the charge -1. The symbol for this ion is I⁻¹, and the name is iodide. The number of electrons in this ion is 7.
Explanation:
Hello,
In this case, we have to consider iodine has the capacity to accept the electrons lost by other elements such as metals or hydrogen by becoming negatively charged. Such phenomena makes iodine to form an anion (negatively charged) with the charge -1, since it only needs one electron to attain the octet. Moreover, the symbol of such ion is I⁻¹ and its name is iodide. By cause of the aforementioned, the number of electrons it has is 7 since at its outer shell seven electrons are found (see electron configuration Kr,5s²,5p⁵).
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Chemical reaction is the basis of life for living organisms; no organism can remain alive without the occurrence of chemical reactions.
Chemical reactions that occur in the living organisms are called biochemical reactions, these reactions are needed for the organism to grow, develop, survive and remain alive; when the chemical reactions stop the organism die.
For instance, to remain alive one has to eat. The food eaten can not be useful to the body if the digestive enzymes do not carry out chemical reactions on it and convert it to a form that can easily enter the blood where it is needed.
Answer: There are 
molecules present in 7.62 L of 
at 
and 722 torr.
Explanation:
Given : Volume = 7.62 L
Temperature = 
Pressure = 722 torr
1 torr = 0.00131579
Converting torr into atm as follows.
Therefore, using the ideal gas equation the number of moles are calculated as follows.
PV = nRT
where,
P = pressure
V = volume
n = number of moles
R = gas constant = 0.0821 L atm/mol K
T = temperature
Substitute the values into above formula as follows.
According to the mole concept, 1 mole of every substance contains 
atoms. Hence, number of atoms or molecules present in 0.244 mol are calculated as follows.
Thus, we can conclude that there are molecules present in 7.62 L of at and 722 torr.
