<span>Anthracite is also referred to as hard coal because it is so hard and pure. It is very hard and highly compacted with variety of coal that has submetallic luster. It has highest carbon content, the lowest impurities, and highest density of energy of all the coal deposits.</span>
Answer: PV = nRT
A gas at STP... This means that the temperature is 0°C and pressure is 1 atm.
R is the gas constant which is 0.08206 L*atm/(K*mol)
Rearranging for volume
V = nRT/P
The temperature and number of moles are held constant. This means that this uses Boyle's Law. (The ideal gas law could be manipulated to give us this result when T and n are held constant.)
PV = k
where k is a constant.
This means that
P₁V₁ = k = P₂V₂
P₁V₁ = P₂V₂
(1 atm) * (1 L) = (2 atm) * V₂
V₂ = 0.5 L
The new volume of the gas is 0.5 L.
Explanation:
Protons/Electrons: 92
Neutrons: 140
***REMEMBER: There is always the same amount of protons and electrons. :)
Half-life is defined as the amount of time it takes a given quantity to decrease to half of its initial value. The equation to describe the decay is
Nt=N0(1/2)
where N0 is the initial quantity, Nt is the remaining quantity after time t, t1/2 is the half-time. So work out the equation, t1/2 = t (-ln2)/ln(Nt/N0) = 11.5*(-ln2)/ln(12.5/100) = 3.83 days
