Which noble gases is closest to magnesium? On the periodic table? What must happen if a magnesium atom for it to have an electron arrangement similar to that of a noble gas?

Neon and loose electrons

Explanation:

Magnesium has an electron configuration of 2e 8e 2e, and Neon is 2e,8e. For Mg to have a similar electron arrangement it must loose its two valence electrons and make it an ion.

Noble neon gas is the closest.

Explanation:

noble Neon  gas

The Magnesium would have to lose two electrons

1. 1 mole of anything contains 6.022x10^23 pieces  

d  

2. a  

3. c, number  

5. 1.24x10^24atoms / 6.022x10^23atoms/mole = 2moles h2 atoms  

6. fe2br3 mass = 2moles x mass fe + 3 moles x mass br  

molar mass = grams / number of moles = g/mole  

to find moles = g / molar mass  

to find mass = g = molar mass / moles