Question

1-How many atoms are present in 4.0mol of sodium?

2-Convert 3.01 x 1023 atoms of Silicon to moles of Silicon?

Answer 1

1=2.4*10^24 atoms NA

2= .49983394 round this to .500

Hope this helps!

Answer 2

Part 1: If 1 mol = 6.022 x 10^23 atoms of anything, including Na, then,

4.0 mol Na = 4 x 6.022 x 10^23 atoms Na = 2.4 x 10^24 atoms Na

Part 2: 3.01E23 / 6.022E23 and the answer comes out to .49983394 you would then round this to .500 with significant figures. Hope I helped. :)