<span>STP means standard temperature
and pressure at 0°C (273K) and 1 atm (atmosphere). The density of the unknown
gas is 0.63 gram per liter. The deal gas equation is PV = nRT. The n is the
numer of moles and can be represented as mass of the gas, m, divided by the
molar mass, c. so we have,</span>
PV = nRT
PV = (m/c)RT
Since the density is d = m/V
Pc = (m/V)RT
Pc = dRT
c = drT/P
substitute the values into the equation,
c = [(0.63g/L)(0.08206
L-atm/mol-K)(273K)]/(1atm)
<u>c = 14.11 g/mol</u>
Atoms are generally neutral because they have an equal amount of protons and electrons.
Answer : The time passed in years is 
Explanation :
Half-life of carbon-14 = 5730 years
First we have to calculate the rate constant, we use the formula :
Now we have to calculate the time passed.
Expression for rate law for first order kinetics is given by:
where,
k = rate constant = 
t = time passed by the sample = ?
a = initial amount of the reactant disintegrate = 15.3
a - x = amount left after decay process = 14.8
Now put all the given values in above equation, we get
Therefore, the time passed in years is
Answer:
98.8
Explanation:
CsF + XeF6 --> CsXeF7
37.8g ................. ?g
37.8g CsF x (1 mol CsF / 151.9g CsF) x (1 mol CsXeF7 / 1 mol CsF) x (397.2g CsXeF7 / 1 mol CsXeF7) = 98.8g CsXeF7 .......... to three significant digits
