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:
Explanation:
a ) false.
NH₃ is more polar molecule than PH₃ so inter-molucular attraction is greater in NH₃ ( hydrogen bond ) . Hence vapour pressure is low for NH₃ .
b ) false .
The average kinetic energy of boiling water molecules is lower on a mountaintop than it is at sea level. It is so because water boils at lower temperture on mountain and kinetic energy of molecules depends upon temperature .
c ) false
vapour pressure depends upon temperature .
d ) True
CCl4 is more volatile than CBr4
e ) false
vapour pressure increases as temperature increases.
Answer:
Your question is half unfinished, regarding the chromium III oxide the correct option that expresses the inorganic formula of said compound is "A"
Explanation:
In the reaction an initial salt reacts giving as product water vapor, nitrogen gas and an oxide that is chromium oxide.
Chromium oxide is an oxide that adopts the structure of corundum, compact hexagonal. It consists of an anion oxide matrix with 2/3 of the octahedral holes occupied by chromium. Like corundum, Cr2O3 is a tough, brittle material.
It is used as a pigment, green in color.
Answer:
How are we supposed to answer that if there is nothing to see
Explanation:
