2Sr(s)+O2(g)→2SrO(s) calculate how many grams of the product form when 16.4 of Sr completely reacts.

Assume that there is more than enough of the other reactant.

Mass = 19.68 g

Explanation:

Given data:

Mass of product formed = ?

Mass of Sr  16.4 g

Solution:

Chemical equation:

2Sr + O₂      →    2SrO

Number of moles of Sr:

Number of moles = mass /molar mass

Number of moles = 16.4 g/ 87.62 g/mol

Number of moles = 0.19 mol

Now we will compare the moles of Sr with SrO.

                     Sr           :         SrO

                      2           :           2

                    0.19        :         0.19

Mass of Sr:

Mass = number of moles × molar mass

Mass = 0.19 mol × 103.62 g/mol

Mass = 19.68 g

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.