What is the mass in grams of 0.40 moles of sodium borohydrate NaBH4

Mass = 15.12 g

Explanation:

Given data:

Mass of sodium borohydride = ?

Number of moles of sodium borohydride =0.40 mol

Solution:

Formula:

Mass = number of moles / molar mass

Molar mass of sodium borohydride = 37.8 g/mol

By putting values,

Mass = 0.40 mol × 37.8 g/mol

Mass = 15.12 g

(b) which contains higher levels of vitamin b, oranges or spinach?

explanation:

you can eliminate a, c, and d because they are questions based on opinions.

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.