You want to divide by avagadros number (6.22 x 10^23). This will cancel the atoms unit and give moles, moles of Iridium. Now you want to calculate the atomic mass of Iridium which is in units of grams per mole. Multiply these two numbers and the moles will cancel giving you grams.
Setting up a dimension analysis type of thing helps tremendously. See what you have to cancel in order to get what you want. We canceled the atoms, then we canceled the moles, and then we got grams.
The number of protons is equal to the atomic number of every element in the periodic table.
Example: The atomic number of Niobium (Nb) is 41. Therefore, the number of protons is also 41.
The volume becomes two. You have to use the equation P1 x V1 = P2 x V2
P is pressure and V is volume.
P1 = 50 P2 = 125
V1 = 5 V2 = v (we don't know what it is)
Then set up the equation:
50 times 5 = 125 times v
250 = 125v
the divide both sides by 125 and isolate v
2 = v
Therefore the volume is decreased to 2.
Also, Boyle's Law explains this too: Volume and pressure are inversely related, This means that when one goes up the other goes down (ie when pressure increases volume decreases and vice versa). Becuase the pressure went up from 50 KPa tp 125 KPa the volume had to decrease.
Answer:
0.017mole
0.0033M
Explanation:
Given parameters:
Formula of the compound:
Mg(ClO₃)₂
Mass of the sample = 3.24g
Unknown:
Number of moles of the sample = ?
Molarity = ?
Solution:
The number of moles of any substance is given as:
Number of moles = 
Molar mass of Mg(ClO₃)₂ = 24 + 2[35.5 + 3(16)] = 191g/mol
Number of moles = 
= 0.017mole
Molarity is the number of moles of a solute in a solution:
Molarity = 
Volume given = 5.08L
Molarity = 
= 0.0033M
