What mass of water can be obtained from 4.0 g of h2 and 16 g of o2?

2 h2 + o2 > 2 h2o

18 g
36 g
54 g
9 g

18 grams of water, will be produced from 4 g of H₂ and 16g of O₂

Explanation:

Reaction: 2H₂ + O₂  ⇒  2H₂O

Moles = Mass / Molar mass

Molar mass H₂ = 2g/m

Molar mass O₂ = 32 g/m

4g /2g/m = 2moles

16g / 32 g/m = 0.5 moles

Ratio is 2:1

For 2 moles of hydrogen, I need 1 mol of oxygen; I have 2 moles of H₂, but I only have 0.5 of O₂, so the O₂ is the limiting reagent.

1 mol of O₂ produces 2 mol of water

0.5 moles of O₂ will produce, the double → 1 mol of water.

Molar mass of water is 18 g/m

1 mol . 18 g/m = 18 g

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.

they are all solids.