P = 2.30 atm
Volume in liter = 2.70 mL / 1000 => 0.0027 L
Temperature in K = 30.0 + 273 => 303 K
R = 0.082 atm
molar mass O2 = 31.9988 g/mol
number of moles O2 :
P * V = n * R* T
2.30 * 0.0027 = n * 0.082 * 303
0.00621 = n * 24.846
n = 0.00621 / 24.846
n = 0.0002499 moles of O2
Mass of O2:
n = m / mm
0.0002499 = m / 31.9988
m = 0.0002499 * 31.9988
m = 0.008 g
Answer:
45 neutrons
Explanation:
Bromine has 35 protons and a mass number of 80. a) How many neutrons does the atom of bromine have? The mass number = protons + neutrons. Bromine has a mass number of 80 and 35 protons so 80-35 = 45 neutrons.
Answer:
See below
Step-by-step explanation:
You won't see much happening. The solution is saturated, so the salt will fall to the bottom of the container and sit there. It will not dissolve.
However, at the atomic level, Na⁺ and Cl⁻ ions are being pulled from the surface of the crystals and going into solution as hydrated ions. At other places, Na⁺ and Cl⁻ ions are returning to the surface of the crystals.
The process is
NaCl(s) ⇌ Na⁺(aq) + Cl⁻(aq)
The rates of the forward and reverse processes are equal, so you see no net change.
1. E. None of the Above
2. D. x + y
Answer: Nitrogen
Explanation: Nitrogen has an atomic number of 7 and an atomic mass of about 14 u
