Identify the blocks and groups of elements in the periodic table

What is the percent composition of ca(oh)2? 37.7% ca, 53.0% o, and 10.3% h 45.5% ca, 38.2% o, and 16.3% h 54.0% ca, 43.0% o, and 2.7% h 64.7% ca, 27.0% o, and 8.3% h

Which terms are used to identify pure substances

Does the number of ions in solution increase, decrease, or remain constant? it continuously decreases. it continuously increases. it decreases at first, then increases. it increases at first, then decreases.