A 1.555 g sample of baking soda decomposes with heat to produce 0.991 g Na2CO3. What is the percent yield of sodium carbonate, Na2CO3?

Explanation:

Baking soda decomposes to produce sodium carbonate .

2NaHCO₃  = Na₂CO₃ + CO₂ + H₂O.

2 x 84 g          106 + 10 x 18  g

Molecular mass of Na₂CO₃ .10H₂O = 286

168 g baking soda  produces 286  g sodium carbonate

1.555g baking soda will produce 286 x 1.555 / 168

= 2.647 g

Percentage yield = actual yield / theoretical yield x 100

= ( .991 /2.647 ) x 100

= 37.43 %.

alkaline metals are lithium, sodium, rubidium, potassium, cesium and francium.

alkali metals have electronegativity from 0.7 to 1, lowest in periodic table of elements, which means that alkali metals (i group in periodic table) has positive oxidation number in compounds.

electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.

alkaline metals (far left in main group) have lowest ionizations energy and easy remove valence electrons,

for example, potassium is the alkali metal and has a single valence electron in the outer electron shell.

electron configuration of potassium is: ₁₉k 1s²2s²2p⁶3s²3p⁶4s¹.

they can not exist alone in nature, because they are very reactive.