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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.
Iridium-192 is used in cancer treatment, a small cylindrical piece of 192 Ir, 0.6 mm in diameter (0.3mm radius) and 3.5 mm long, is surgically inserted into the tumor. if the density of iridium is 22.42 g/cm3, how many iridium atoms are present in the sample?
Let us start by computing for the volume of the cylinder. V = π(r^2)*h where r and h are the radius and height of the cylinder, respectively. Let's convert all given dimensions to cm first. Radius = 0.03 cm, height is 0.35cm long.
V = π * (0.03cm)^2 * 0.35 cm = 9.896*10^-4 cm^3
Now we have the volume of 192-Ir, let's use the density provided to get it's mass, and once we have the mass let's use the molar mass to get the amount of moles. After getting the amount of moles, we use Avogadro's number to convert moles into number of atoms. See the calculation below and see if all units "cancel":
9.896*10^-4 cm^3 * (22.42 g/cm3) * (1 mole / 191.963 g) * (6.022x10^23 atoms /mole)
= 6.96 x 10^19 atoms of Ir-122 are present.
Answer:
electric charge
Explanation:
A nuclide is represented by the name of the element, preceded by the mass number (A) as a superscript on the left and the atomic number (Z) as subscript.
On the right, as a superscript is the electrical charge (e.g. +2) and is following the element name.