I think the correct form of the equation is given as:
a = a0 * (0.9)^t
where t is an exponent of 0.9 since this is an
exponential decay of 1st order reaction
Now to solve for the half life, this is the time t in
which the amount left is half of the original amount, therefore that is when:
a = 0.5 a0
Substituting this into the equation:
0.5 a0 = a0 * (0.9)^t
0.5 = (0.9)^t
Taking the log of both sides:
t log 0.9 = log 0.5
t = log 0.5 / log 0.9
t = 6.58 years
Answer:
half life = 6.58 years
Kg = 3.20 x 10^4 troyounces x 0.0311kg/1 troy ounce = 995.2 kg
Answer:
Count the number of valence electrons
Explanation:
Explanation:
1 literThe total of water is equal to 1000.0 g of water
we need to find the molality of a solution containing 10.0 g of dissolved in Na₂S0₄1000.0 g of water
1. For that find the molar mass
Na: 2 x 22.99= 45.98
S: 32.07
O: 4 x 16= 64
The total molar mass is 142.05
We have to find the number of moles, y
To find the number of moles divide 10.0g by 142.05 g/mol.
So the number of moles is 0.0704 moles.
For the molarity, you need the number of moles divided by the volume. So, 0.0704 mol/1 L.
The molarity would end up being 0.0704 M
The molality of a solution containing 10.0 g of Na2SO4 dissolved in 1000.0 g of water is 0.0704 Mliter
Because carbon has two double bonds which is equal to 8 electrons so therefore the octet rule is fulfilled.
