1. how many atoms are there in 1.7 mol ca?

There are atoms in 1.7 mol Ca

Solution:

Initially we have to convert the given mass of calcium to moles of calcium, using its molar mass (referring to a periodic table, this is 40.08  g/mol

Using Avogadro's number, as

We can calculate the number of atoms present by

trigonal pyramidal

tetrahedral

trigonal planar

bent