Explanation:
As we know that sum of only total number of protons are also known as atomic number of an atom. And, the sum of total number of protons and neutrons is known as atomic mass of an atom.
Number of protons help in determining the identity of an atom whereas the number of neutrons can be same for two or more number of atoms. But the number of protons will remain the same for a particular atom and for its isotopes.
For example, tex]^{1}_{1}H[/tex] and
are isotopes and each of them contains 1 proton.
thus, we can conclude that the number of protons in their nuclei would allow you to determine whether two atoms are of the same or different elements.
Answer: There are 0.5 grams of barium sulfate are present in 250 of 2.0 M
solution.
Explanation:
Given: Molarity of solution = 2.0 M
Volume of solution = 250 mL
Convert mL int L as follows.

Molarity is the number of moles of solute present in liter of solution. Hence, molarity of the given
solution is as follows.

Thus, we can conclude that there are 0.5 grams of barium sulfate are present in 250 of 2.0 M
solution.
Answer:
6.48 L
Explanation:
From the question,
Applying
PV/T = P'V'/T'......................... Equation 1
P = initial pressure of the helium balloon, V = Initial volume of the balloon, T = Initial temperature of the balloon, P' = Final pressure of the balloon, T' = Final temperature of the balloon, V' = Final volume of the balloon.
make V' the subject of the equation
V' = PVT'/P'T......................... Equation 2
Given: P = 1 atm, V = 4.5 L, T' = 253 K, T= 293 K, P' = 0.6 atm
Substitute these values into equation 2
V' = (4.5×1×253)/(0.6×293)
V' = 1138.5/175.8
V' = 6.48 L