How many moles are in 45.8 g of calcium nitrate, Ca(NO3),?

the number of moles is 0.279

Explanation:

The calculation of the number of moles of calcium nitrate, is given  below;

As We know that

Number of moles = mass of substance ÷ molecular weight

where

Mass of substance is 45.8g

And, the molecular weight is 164.088

so,

= 45.8 g ÷ 164.088

= 0.279moles

Thus , the number of moles is 0.279

We simply used the above formula so that the accurate value could arrive

its first and third is your answer i did the qustion the fourth isnt right