What is the molarity of the following? 23g of a solution ba br2 in a 2.3l of solution 15g of cas in 2 l of solution

Molarity = number mole of substances/ Volume solution (L)

To find number of mole we need to find Molar mass , at first.

1) M(BaBr2)= M(Ba) +2 M(Br) = 137.3 + 2*80.0= 197.3 g/mol
23g BaBr2 *(1mol BaBr2/197.3 g BaBr2) = 0.12 mol BaBr2
Molarity (BaBr2 solution) =0.12 mol/2.3 L≈0.052 mol/L ( BaBr2 solution)
Molarity of BaBr2 solution = 0.052 M

2) M(CaS)= M(Ca)+M(S)= 40.1+32.1=72.2 g/mol
15 g CaS*(1mol CaS/72.2 g CaS)= 0.21 mol CaS
Molarity (CaS solution) = 0.21 mol/2 L≈ 0.11 mol/L (CaS solution)
Molarity of CaS solution = 0.11 M

the catch is that the top numbers are atomic masses the bottom numbers are the numbers of protons and electrons in an uncharged atom. they are the number of that atoms as you would find them on the periodic table. further, the numbers on the left are used to determine the missing numbers on the right

so here we go

atomic mass

239 + 1 = y + 134 + 3 combine like terms

240 = y + 137             subtract 137 from both terms

240 - 137 = y

103 = y

atomic number

94 = z +54 + 0

94 = z + 54               subtract 54 from both sides.

40 = z

answer