Explanation:
A.ph 6 B. correct ph goes in a scale up to 14 below 7 is acidic above 7 is basic and in the middle is newtral when they say pH they are asking how acidic is it when they ask for pOH they are asking how basic it is pH is calculated using logs as is pOH so ans
12.65
Answer:
0.0738 M
Explanation:
HNO3 +LiOH = LiNO3 + H2O
Number of moles HNO3 = number of moles LiOH
M(HNO3)*V(HNO3) = M(LiOH)*M(LiOH)
M(HNO3)*50.0mL = 0.100M*36.90 mL
M(HNO3) = 0.100*36.90/50.0 M = 0.0738 M
Answer:
10 neutrons
Explanation:
N=Z-A ie. number of neutrons=mass number-atomic number
N=19-9=10
4 after solving =0.004800 where 4,800 is the significant number
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.
