Answer:
17
Explanation:
the atomic mass is away protons + neutrons, electrons are neglatable.
Answer: If the outermost shell has 1–4 electrons, it is a metal.
If the outermost shell has 5–7 electrons, it is a non-metal.
To solve this we assume
that the gas inside is an ideal gas. Then, we can use the ideal gas
equation which is expressed as PV = nRT. At a constant pressure and number of
moles of the gas the ratio T/V is equal to some constant. At another set of
condition of temperature, the constant is still the same. Calculations are as
follows:
T1 / V1 = T2 / V2
T2 = T1 x V2 / V1
T2 = 280 x 20.0 / 10
<span>T2 = 560 K</span>
We can use the ideal gas law equation to find the volume of the gas.
PV = nRT
P - pressure - 400 kPa
V - volume
n - number of moles - 4.00 mol
R - universal gas constant - 8.314 Jmol⁻¹K⁻¹
T - temperature - 300.0 K
substituting these values in the equation
400 000 Pa x V = 4.00 mol x 8.314 Jmol⁻¹K⁻¹ x 300.0 K
V = 24.9 dm³
Volume is 24.9 dm³
