How many moles of oxygen are in 523 g of lime, Ca(OH)2 ?

Hey there!

First we need to find the molar mass of Ca(OH)₂.

Ca: 1 x 40.078

O: 2 x 16

H: 2 x 1.008

           74.094 grams

Find how many moles are in 523 grams of Ca(OH)₂.

523 ÷ 74.094 = 7.06 moles

There are 2 atoms of oxygen in each molecule of Ca(OH)₂.

7.06 x 2 = 14.12  

523g of Ca(OH)₂ contains 14.12 moles of oxygen.

Hope this helps!

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