Some ocean currents are caused by differences in the density of water from place to place around the globe. what two factors cause differences in ocean water density

The density of ocean water is affected by differences in water temperature and amount of dissolved salts. Some animals use ocean currents to move from one area of the ocean to another.

Mass = 42.88 g

Explanation:

Given data:

Mass of iron = 100 g

Mass of O₂ = ?

Solution:

Chemical equation:

4Fe + 3O₂       →    2Fe₂O₃

Number of moles of Iron:

Number of moles = mass/molar mass

Number of moles = 100 g/ 55.85 g/mol

Number of moles = 1.79 mol

Now we will compare the  moles iron with oxygen.

                               Fe          :              O₂

                                 4            :               3

                                 1.79        :           3/4×1.79 = 1.34 mol

Mass of oxygen used:

Mass = number of moles × molar mass

Mass = 1.34 mol × 32 g/mol

Mass = 42.88 g