You can find the ideal gas law (the formula) constants (r) on the internet :)
Answer:
The atomic mass of methane (CH4)is 12 amu for the carbon plus 4 x 1 amu for the four hydrogens, for a total of 16 amu. Therefore, the molar mass of methane is 16g.
First find the number of moles of KSCN is in 4.40g of KSCN
1. Number of moles = mass given (4.40g) / molecular weight(MW) (KSCN)
- to calculate MW, look for each element in the periodic table and add their atomic weight
2. Convert 200mL to liters
3. Concentration = number of moles/ volume in liters from (#2)
Exocytosis : exo- means outside , -cyte means cell
Moles= mass/Mr
Moles= 3.82/40
Moles= 0.0955 mol
