Atomic mass is the decimal number that is on the periodic table...
Boron's atomic mass is 10.81
Word equation: magnesium chloride + bromine -> magnesium bromide + chlorine
balance equation: MgCl2 + 2Br -> MgBr2 + 2Cl
Force acting on the body when the body is at rest the net formals is given
So, you need to have same ammount of atoms on the left and on the right side of the equation. You need to count the ammount of attoms of every substance on the left, and make sure that on the right side the ammount is same. For example in the 1st one it’s 6Sn+2P4=2Sn3P4, so that you have 6atoms of Sn on the left and 6 atoms of Sn on the right, same with the P
