The nuclear equation that describes the alpha decay of Polonium-210 can be written like this:
210/
84Po→206/82Pb+4/2 He
<span>1.15x10^24 molecules of hypothetical substance b
Making the assumption that each molecule in hypothetical substance a reacts to produce a single molecule of hypothetical substance b, then the number of molecules of substance b will be the number of moles of substance a multiplied by avogadro's number. So
Moles hypothetical substance a = 29.9 g / 15.7 g/mol = 1.904458599 moles
This means that we should also have 1.904458599 moles of hypothetical substance b. And to get the number of atoms, multiply by 6.0221409x10^23, so:
1.904458599 * 6.0221409x10^23 = 1.146892x10^24 molecules.
Rounding to 3 significant figures gives 1.15x10^24</span>
The joules required to heat 2L of water in a pot from 20 c to the boiling point of water is calculated using the following formula
Q= MC delta T
M = mass = density x volume( 2 x 1000= 2000ml)
M = 1g/ml x2000 ml = 2000g
C = specific heat capacity = 4.18 g/c
delta T = change in temperature = 100 c ( boiling point of water) - 20 c = 80 c
Q is therefore = 2000 g x 4.18 j/g c x 80c = 668800j
Best Answer: o.n. = 70 means 70% isoctane for which o.n. = 100 and 30% of heptane for which o.n. = 0
