How many moles of Ca are in 1.25x1023 atoms? We used two conversion factors in this unit, they are provided below. It is your responsibility to know which conversion factor to use!

Avogadro’s number: 6.02x1023 atoms = 1 mole

Molar mass of calcium: 40.078 g Ca = 1 mol Ca

A. 3.12x10^21 mol

B. 0.21 mol

C. 3.12 mol

D. 0.21x10^21 mol

B. 0.21 mol

Math

Pre-Algebra

Order of Operations: BPEMDAS

Chemistry

Atomic Structure

Step 1: Define

1.25 × 10²³ atoms Ca

Step 2: Identify Conversions

Avogadro's Number

Step 3: Convert

Step 4: Check

Follow sig fig rules and round. We are given 3 sig figs.

0.207572 mol Ca ≈ 0.208 mol Ca

the seeing the electronic configuration we can say that the element is fluorine.

fluorine is the most electronegative element in the periodic table.

but by only seeing the configuration we cannot say about its reactivity because we don't know if its configuration after excitation or by addition of electrons.

but if not then, it is the lightest halogen and exists as a highly toxic pale yellow diatomic gas at standard conditions. as the most electronegative element, it is extremely reactive: almost all other elements, including some noble gases, form compounds with fluorine.