A chermist weighs out 400.0 g of Ca How many moles of Ca is this?

Explanation:

To find out the number of moles we use the formula

where

n is the number of moles

M is the molar mass

m is the mass of the substance

From the question

m = 400 g

M of Ca = 40 g/mol

We have

We have the final answer as

Hope this helps you

when [oh-] is 10-5  m, and [h3o+] is 10-9  m, the poh is 5 and ph is 9. again in both cases the sum of ph and poh is 14. however, the hydrogen ion concentration is not always going to be equal to exactly 1 x 10 raised to a negative number. for example, we skipped over the value of 2.0 x 10-7.