Answer: number of atoms is 5.21 · 10^24
Explanation: Atomic mass of Be is 9.012 g/mol.
Number of moles n = m/M = 78.0 g / 9.012 g/mol =
Multiply this with Avogadro number Na = 6.022*10^23 1/mol
Answer: increasing number of protons increases the positive charge of the nucleus.
Explanation: because as the electronegativity moves from left to right on the periodic table the protons do increase to make it into a positive charge.
Answer:
Explanation:
Given : Density - 2.41 g/liter
Temperature - 25° C
Pressure : 770 mm Hg
R = 0.0821 L atm mol-¹K-¹
Find : Molecular mass of gas
Solution : Ideal gas equation with respect to density will be : PM = dRT. In the formula, P is pressure, M is molecular mass, d is density, R is gas constant and T is temperature.
Keeping the values in equation-
Pressure : 770 mm Hg = 1 atm
Temperature : 273 + 25 = 298 K
M = dRT/P
M = (2.41*0.0821*298)/1
M = 58.96 gram/mol
Thus, the molecular mass of gas is 58.96 gram/mol.
A residue from a gunshot is most likely gun powder, which tells you what kind of bullet was shot and the type of gun that was used to shoot the target/victim/person. Some complications may be that there is more than one gun or weapon which uses that residue, so it may be hard to pinpoint it and the bullet can't really tell you who it is unless there's DNA on the bullet, and the chemicals of the bullet may even destroy evidence.