Answer:
247.2g
Explanation:
Using the general gas law equation as follows:
PV = nRT
Where;
P = pressure (atm)
V = volume (L)
n = number of moles (mol)
R = gas law constant (0.0821 Latm/molK)
T = temperature (K)
According to the information in this question, a fuel tank contains 150. L (V) of H2 gas at 20.0 atm (P) at 25.0˚C (T)
Temperature = 25°C = 25 + 273 = 298K
Using PV = nRT
20 × 150 = n × 0.0821 × 298
3000 = 24.4658n
n = 3000/24.4658
n = 122.62
n = 122.6mol
Using the formula, mole = mass/molar mass, to find the mass of H2 gas.
Molar mass of H2 = 1.008(2)
= 2.016g/mol
122.6 = mass/2.016
mass = 122.6 × 2.016
mass = 247.2g.
Answer:
There are 8Si atoms and 16 O atoms per unit cell
Explanation:
From the question we are told that:
Edge length 
Density 
Generally the equation for Volume is mathematically given by



Where
Molar mass of (SiO2) for one formula unit


Therefore
Density of Si per unit length is


Molar mass of (SiO2) for one formula unit


Therefore
There are 8Si atoms and 16 O atoms per unit cell
Answer:
Letter B.
Explanation:
Changing its direction and climbing a steep incline can't be proven only by the graph info. You can see that it's speed isn't constant in the graph.
We have letter B left.