Answer:
Object 4 in the example
Explanation:
For simplicity and a clearer view of this problem, let's assume that four masses from 1 to 4 have the the masses 2 kg, 4 kg, 6 kg, 8 kg respectively.
According to the second Newton's law, we know that force is directly proportional to both mass and acceleration. The equation representing this is 
.
Notice that all of them have the same acceleration. This means, the greater the mass, the greater the force for a fixed acceleration. Simply speaking, the forces for each of the objects would be 2a, 4a, 6a and 8a respectively.
Since we're interested in the magnitude of the force and not direction, we neglect whether acceleration is positive or negative. This means that object 4 will require the greatest force to move, as it has the greatest mass.
Now to solve this problem, we are given the number of atoms
therefore we must first convert this into number of moles. We can do this by
using the Avogadro’s number. Calculating for number of moles of Carbon:
number of moles Carbon = 21 atoms of carbon (1 mole / 6.022
x 10^23 atoms C)
number of moles Carbon = 3.49 x 10^-23 mol C
Converting this to mass by multiplying the molar mass of
C:
mass Carbon = 3.49 x 10^-23 mol C (12 g / mol)
mass Carbon = 4.18 x 10^-22 g
Therefore the mass of one molecule of Cortisone is:
mass of 1 molecule Cortisone = 4.18 x 10^-22 g / 0.6998
mass of 1 molecule Cortisone = 5.98 x 10^-22 g per molecule
Converting this to mass per 1 mol of Cortisone, by using
again the Avogadro’s number:
mass of 1 mol Cortisone = (5.98 x 10^-22 g / molecule) (<span>6.022
x 10^23 molecules / mol)</span>
mass of 1 mol Cortisone = 360.10 g / mol = molar mass of
cortisone
Answer:
360.10 g / mol
Answer:
0.98 g of H₂
Explanation:
the balanced equation for the reaction is
Mg + 2HCl ---> MgCl₂ + H₂
molar ratio of Mg to H₂ is 1:1
number of Mg moles reacted = 12 g/ 24.3 g/mol = 0.49 mol
according to molar ratio
when 1 mol of Mg reacts 1 mol of H₂ is formed
therefore when 0.49 mol of Mg reacts - 0.49 mol of H₂ forms
therefore mass of H₂ formed = 0.49 mol x 2 g/mol = 0.98 g
mass of H₂ formed is 0.98 g
