121.75 is really really really really really the right answer... For real
Low melting points and boiling points. ...Low enthalpies of fusion and vaporization These properties are usually one or two orders of magnitude smaller than they are for ionic compounds.Soft or brittle solid forms. ...Poor electrical and thermal conductivity.
ANSWER
2 valence electrons
STEP-BY-STEP EXPLANATION:
The electronic configuration is given below as
Looking at the configuration, you will see that the last energy carries 2 electrons
Hence, the valence electrons are 2
The chemical reaction would be as follows:
<span>2Na + S → Na2S
We are given the amount of the reactants to be used in the reaction. We use these to calculate the amount of product. We do as follows:
45.3 g Na ( 1 mol / 22.99 g ) = 1.97 mol Na
105 g S ( 1 mol / 32.06 g ) = 3.28 mol S
The limiting reactant would be Na. We calculate as follows:
1.97 mol Na ( 1 mol Na2S / 2 mol Na ) (78.04 g / mol ) = 76.87 g Na2S produced</span>
D — density
hope this helps !
