<span> (0.20948 x 31.998) / (
(0.78084 x 28.013) +
(0.20948 x 31.998) +
(0.00934 x 39.948) +
(0.000375 x 44.0099) +
(0.00001818 x 20.183) +
(0.00000524 x 4.003) +
(0.000002 x 16.043) +
(0.00000114 x 83.80) +
(0.0000005 x 2.0159) +
(0.0000005 x 44.0128) ) = 0.23140 = 23.140% O by mass </span>
Physical changes occur when the properties of a substance are retained and/or the materials can be recovered after the change. Chemical changes involve the formation of a new substance. Formation of a gas, solid, light, or heat are possible evidence of chemical change.
The density : 21.63 g/L
<h3>Further explanation</h3>
The gas equation can be written

where
P = pressure, atm
V = volume, liter
n = number of moles
R = gas constant = 0.08206 L.atm / mol K
T = temperature, Kelvin
T = 65+273=338 K
P=2.36 atm
MW Iodine gas (I₂)=254
The density :

Answer: d. ends to the scalp
In the croquignole method of wrapping the hair is wrapped and wound from the ends (tip) to the scalp in the overlapping layers. This method is used to produce a physical change in the hair, that is providing a waving or curling pattern to the hair. The curls of hair are usually tighter at the ends and gets larger nearer the scalp.
I believe a solution of Sn(NO3)2 can not be stored in an aluminium container because Aluminium is higher in the reactivity series compared to Tin (Sn). Therefore, Aluminium is more reactive than Tin and hence aluminium will displace Tin from its salt forming Aluminium nitrate and Tin metal. Thus storing Tin nitrate in an aluminium container will cause the "eating away' of the container.