Answer:
0.06mole
Explanation:
Given parameters:
Volume of balloon = 2.5L
T = 343.5K
P = 66.7kPa; in atm gives = 0.66atm
Unknown:
Number of moles of He = ?
Solution:
To solve this problem, we use the ideal gas equation.
It is mathematically expressed as;
Pv = nRT
where p is the pressure
v is the volume
n is the number of moles
R is the gas constant
T is the temperature
0.66 x 2.5 = n x 0.082 x 343.5
n = 0.06mole
Yes cells are the blank unit for all things that are living
Answer: 15.0 moles of
are formed from 30.0 mol of 
Explanation:
The balanced chemical reaction is :
According to stoichiometry :
2 moles of
give = 1 mole of 
Thus 30.0 moles of
will give =
of 
Thus 15.0 moles of
are formed from 30.0 mol of 
Answer:
Taking into account the definition of average atomic mass and isotopes of an element, the information that you need is the masses of its isotopes and their percent abundances.
Each chemical element is characterized by the number of protons in its nucleus, which is called the atomic number Z.
But in the nucleus of each element it is also possible to find neutrons, whose number can vary. The atomic mass (A) is obtained by adding the number of protons and neutrons in a given nucleus.
The same chemical element can be made up of different atoms, that is, their atomic numbers are the same, but the number of neutrons is different. These atoms are called isotopes of the element.
The atomic mass of an element is the weighted average mass of its natural isotopes. Therefore, the atomic mass of an element is not a whole number.
The weighted average means that not all isotopes have the same percentage.
In other words, the atomic masses of chemical elements are usually calculated as the weighted average of the masses of the different isotopes of each element, taking into account the relative abundance of each of them.
Explanation:
Answer:
Work done in Joules = -14865.432J
ΔU = -262.94KJ
Explanation:
The steps are as shown in the attachment