Water containing large amounts of Mg2+and Ca2+ions is said to be hard because it is hard to make soap lather in the water. True False

True

Explanation:

Water is said to be hard when it contains calcium ions or magnesium ions dissolved in it. These ions are able to react with soap in such a way that the soap is prevented from forming lather with the water. Hard water occurs when water passes over calcium or magnesium bearing minerals and dissolves some of it. Hardness due to the presence of calcium ions can easily be removed by boiling the water.

D the percent error included in the data

Explanation:

The standard deviation is the amount that each of the data points very from the average.