C because, its products is heavier than each of its reactants
The percentage error is given by multiplying relative error by 100%.
Therefore, to get the percentage error we need relative error which is given by dividing the absolute error with the actual value.
Absolute error = 0.133
Percentage error = 0.133/5.586 × 100%
= 2.38%
The percentage error is therefore; 2.38%
The Answer is C . The differences in the magnetic force from place to place .
For every 2 mole Mg we need 1 mole O2 ( based on the equation). since there is 4 mole Mg we need 2 mole O2. one mole O2 is 32 gram so 2 mole would be 64 grams.
Mass number = proton number+ neutron number
m=92+143
=235